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+# Phase 01: Database Schema & Backend API - Research
+
+**Researched:** 2026-02-13
+**Domain:** Laravel 10 polymorphic relationships, database schema design, RESTful API endpoints
+**Confidence:** HIGH
+
+## Summary
+
+Phase 1 involves creating a polymorphic `notes` table that can attach to multiple entity types (starting with Members, extensible to future entities like Issues or Finance documents). The implementation follows Laravel 10's standard morphMany/morphTo relationship pattern with proper composite indexing for performance. Admin endpoints will return Blade views (consistent with existing admin controllers), not JSON API responses.
+
+**Primary recommendation:** Use Laravel's native polymorphic relationship methods (`morphMany`/`morphTo`) with composite index on `[notable_type, notable_id]` columns, implement eager loading with `withCount('notes')` to prevent N+1 queries, and use Form Request classes for validation following existing codebase patterns.
+
+## Standard Stack
+
+### Core
+| Library | Version | Purpose | Why Standard |
+|---------|---------|---------|--------------|
+| Laravel Framework | 10.50.0 | Backend framework | Existing codebase version |
+| PHP | 8.1+ | Runtime | Project requirement |
+| Spatie Laravel Permission | ^5.10 | RBAC authorization | Already integrated for role/permission checks |
+
+### Supporting
+| Library | Version | Purpose | When to Use |
+|---------|---------|---------|-------------|
+| Laravel Debugbar | dev only | N+1 query detection | Development environment to verify no performance issues |
+
+### Alternatives Considered
+| Instead of | Could Use | Tradeoff |
+|------------|-----------|----------|
+| Polymorphic relationship | Separate notes tables per entity | Polymorphic provides extensibility; separate tables harder to maintain as features grow |
+| Form Request classes | Inline validation | Form Requests align with existing codebase pattern (see `StoreMemberRequest`) |
+| Blade views | API JSON responses | Admin controllers return views (consistent with `ArticleController`, `DocumentController` patterns) |
+
+**Installation:**
+No new packages required - uses Laravel core features.
+
+## Architecture Patterns
+
+### Recommended Project Structure
+```
+app/
+├── Models/
+│ ├── Note.php # New polymorphic child model
+│ └── Member.php # Add morphMany relationship
+├── Http/
+│ ├── Controllers/
+│ │ └── Admin/
+│ │ └── MemberNoteController.php # New resource controller
+│ └── Requests/
+│ ├── StoreNoteRequest.php # Validation for creating notes
+│ └── UpdateNoteRequest.php # Validation for updating notes
+└── database/
+ └── migrations/
+ └── YYYY_MM_DD_HHMMSS_create_notes_table.php
+
+tests/
+└── Feature/
+ └── Admin/
+ └── MemberNoteTest.php # Feature tests for note CRUD
+```
+
+### Pattern 1: Polymorphic One-to-Many Relationship
+**What:** Notes belong to multiple entity types (Member, future Issue, etc.) using `notable_type` and `notable_id` columns
+**When to use:** When a child model (Note) can attach to multiple parent model types
+**Example:**
+```php
+// Source: https://laravel.com/docs/10.x/eloquent-relationships (Polymorphic Relationships section)
+
+// app/Models/Note.php
+class Note extends Model
+{
+ protected $fillable = [
+ 'notable_type',
+ 'notable_id',
+ 'content',
+ 'author_user_id',
+ ];
+
+ public function notable(): MorphTo
+ {
+ return $this->morphTo();
+ }
+
+ public function author(): BelongsTo
+ {
+ return $this->belongsTo(User::class, 'author_user_id');
+ }
+}
+
+// app/Models/Member.php
+class Member extends Model
+{
+ public function notes(): MorphMany
+ {
+ return $this->morphMany(Note::class, 'notable');
+ }
+}
+
+// Usage
+$member = Member::find(1);
+$notes = $member->notes; // Returns all notes for this member
+```
+
+### Pattern 2: Composite Index for Polymorphic Lookups
+**What:** Single index on both `notable_type` and `notable_id` columns together
+**When to use:** Always for polymorphic relationships - both columns are required for queries
+**Example:**
+```php
+// Source: https://roelofjanelsinga.com/articles/improve-performance-polymorphic-relationships-laravel/
+
+Schema::create('notes', function (Blueprint $table) {
+ $table->id();
+ $table->morphs('notable'); // Creates notable_type, notable_id, and composite index
+ // Alternatively, manual approach:
+ // $table->string('notable_type');
+ // $table->unsignedBigInteger('notable_id');
+ // $table->index(['notable_type', 'notable_id']); // Composite index - order matters!
+
+ $table->longText('content');
+ $table->foreignId('author_user_id')->constrained('users')->cascadeOnDelete();
+ $table->timestamps();
+
+ // Additional indexes for sorting/filtering
+ $table->index('created_at');
+});
+```
+
+### Pattern 3: Prevent N+1 with `withCount()`
+**What:** Eager load relationship counts in a single query
+**When to use:** When displaying lists with relationship counts (member index showing note count)
+**Example:**
+```php
+// Source: Existing codebase app/Http/Controllers/Admin/ArticleCategoryController.php
+
+// Admin controller - member list
+public function index(Request $request)
+{
+ // withCount prevents N+1 by adding notes_count column via subquery
+ $members = Member::withCount('notes')
+ ->orderBy('created_at', 'desc')
+ ->paginate(20);
+
+ return view('admin.members.index', compact('members'));
+}
+
+// In Blade view
+@foreach($members as $member)
+
{{ $member->notes_count }} |
+@endforeach
+```
+
+### Pattern 4: Form Request Validation
+**What:** Separate validation classes with `authorize()` and `rules()` methods
+**When to use:** All admin controller actions that modify data
+**Example:**
+```php
+// Source: Existing codebase app/Http/Requests/StoreMemberRequest.php
+
+// app/Http/Requests/StoreNoteRequest.php
+class StoreNoteRequest extends FormRequest
+{
+ public function authorize(): bool
+ {
+ // Reuse existing admin middleware - all admin users can write notes
+ return $this->user()->hasRole('admin')
+ || !$this->user()->getAllPermissions()->isEmpty();
+ }
+
+ public function rules(): array
+ {
+ return [
+ 'content' => 'required|string|min:1',
+ 'notable_type' => 'required|string|in:App\Models\Member',
+ 'notable_id' => 'required|integer|exists:members,id',
+ ];
+ }
+}
+
+// Controller usage
+public function store(StoreNoteRequest $request)
+{
+ $validated = $request->validated();
+ // Validation already passed, data is clean
+}
+```
+
+### Pattern 5: Audit Logging for Note Actions
+**What:** Manual audit log calls in controller actions (not observers)
+**When to use:** After successful data mutations
+**Example:**
+```php
+// Source: Existing codebase app/Http/Controllers/BudgetController.php
+
+use App\Support\AuditLogger;
+
+public function store(StoreNoteRequest $request)
+{
+ $note = Note::create([
+ 'notable_type' => $request->notable_type,
+ 'notable_id' => $request->notable_id,
+ 'content' => $request->content,
+ 'author_user_id' => $request->user()->id,
+ ]);
+
+ AuditLogger::log('note.created', $note, [
+ 'notable_type' => $request->notable_type,
+ 'notable_id' => $request->notable_id,
+ 'author' => $request->user()->name,
+ ]);
+
+ return redirect()->back()->with('status', '備忘錄已新增');
+}
+```
+
+### Pattern 6: Admin Route Registration
+**What:** Group admin routes under `/admin` prefix with `auth` and `admin` middleware
+**When to use:** All administrative functionality
+**Example:**
+```php
+// Source: Existing codebase routes/web.php
+
+Route::middleware(['auth', 'admin'])->prefix('admin')->name('admin.')->group(function () {
+ // Nested resource route for member notes
+ Route::resource('members.notes', MemberNoteController::class)
+ ->only(['store', 'update', 'destroy']);
+});
+
+// Routes generated:
+// POST /admin/members/{member}/notes → admin.members.notes.store
+// PATCH /admin/members/{member}/notes/{note} → admin.members.notes.update
+// DELETE /admin/members/{member}/notes/{note} → admin.members.notes.destroy
+```
+
+### Anti-Patterns to Avoid
+- **Magic strings for status values:** Use class constants like `Note::STATUS_ACTIVE`, not hardcoded strings
+- **Single-column indexes on polymorphic tables:** Always use composite `[type, id]` index, not separate indexes
+- **Lazy loading in lists:** Always use `withCount()` or `with()` to eager load relationships
+- **Inline validation:** Use Form Request classes consistently with existing codebase
+- **API resources for admin endpoints:** Admin controllers return Blade views, not JSON (only `/api/v1/*` routes use API resources)
+- **Automatic audit logging:** This codebase calls `AuditLogger::log()` manually in controllers, not via model observers
+
+## Don't Hand-Roll
+
+| Problem | Don't Build | Use Instead | Why |
+|---------|-------------|-------------|-----|
+| Polymorphic relationships | Custom join tables with type columns | Laravel `morphMany`/`morphTo` | Handles fully qualified class names, supports eager loading, integrates with query builder |
+| N+1 query prevention | Manual caching or query optimization | `withCount()`, `with()` eager loading | Laravel optimizes to single subquery, works with pagination |
+| Polymorphic indexes | Separate indexes on `_type` and `_id` | `$table->morphs('notable')` or composite `index(['type', 'id'])` | MySQL/PostgreSQL can only use composite index when querying both columns together |
+| Request validation | Try/catch with manual validation | Form Request classes with `authorize()` and `rules()` | Automatic 422 responses, clean controller code, reusable validation logic |
+| Audit logging | Custom logging to text files | `AuditLogger::log($action, $model, $metadata)` | Already implemented, stores structured JSON metadata, searchable in database |
+
+**Key insight:** Laravel's polymorphic relationship methods handle edge cases like proper class name storage (can use morph map to decouple), query scoping, and eager loading optimizations. Composite indexing is critical because MySQL/PostgreSQL cannot use separate indexes for queries requiring both `notable_type = 'X' AND notable_id = Y`.
+
+## Common Pitfalls
+
+### Pitfall 1: Missing Composite Index on Polymorphic Columns
+**What goes wrong:** Queries for notes on a specific member become slow (full table scans) when notes table grows beyond ~10,000 records
+**Why it happens:** Developers create separate indexes on `notable_type` and `notable_id` instead of a single composite index
+**How to avoid:** Use `$table->morphs('notable')` which automatically creates the composite index, or manually use `$table->index(['notable_type', 'notable_id'])`
+**Warning signs:** Slow member detail pages when loading notes, database query time over 100ms for note lookups
+
+**Source:** [Roelof Jan Elsinga - Improve query performance for polymorphic relationships](https://roelofjanelsinga.com/articles/improve-performance-polymorphic-relationships-laravel/)
+
+### Pitfall 2: N+1 Queries When Displaying Note Counts
+**What goes wrong:** Member list page makes 1 query to fetch members + N queries to count notes for each member (21 queries for 20 members)
+**Why it happens:** Blade views access `$member->notes->count()` without eager loading the count in the controller
+**How to avoid:** Use `Member::withCount('notes')` in controller, then access `$member->notes_count` in Blade (single subquery added to initial fetch)
+**Warning signs:** Laravel Debugbar shows N queries all with same structure (SELECT COUNT(*) FROM notes WHERE notable_id = ?), page load time increases linearly with pagination size
+
+**Source:** [Yellow Duck - Laravel's Eloquent withCount method](https://www.yellowduck.be/posts/laravels-eloquent-withcount-method)
+
+### Pitfall 3: Wrong Column Order in Composite Index
+**What goes wrong:** Composite index `['notable_id', 'notable_type']` is not used by queries filtering on both columns
+**Why it happens:** MySQL uses leftmost prefix rule - index only applies if query filters leftmost column first
+**How to avoid:** Always put `notable_type` first in composite index: `['notable_type', 'notable_id']` because queries always filter by type AND id together
+**Warning signs:** EXPLAIN query shows "type: ALL" (full table scan) even with composite index present
+
+**Source:** [René Roth - Composite indexes in Laravel & MySQL](https://reneroth.xyz/composite-indices-in-laravel/)
+
+### Pitfall 4: Self-Approval in Author Verification
+**What goes wrong:** Note author can modify or delete their own notes without proper authorization checks
+**Why it happens:** Controller checks `if($user->can('edit_notes'))` but doesn't verify `$note->author_user_id != $user->id`
+**How to avoid:** Based on existing codebase pattern with `HasApprovalWorkflow` trait, implement similar check in controller authorization or use Laravel policies
+**Warning signs:** Audit trail shows notes modified by original author when business rule requires separate approver
+
+**Source:** Existing codebase pattern in `app/Traits/HasApprovalWorkflow.php` (self-approval prevention)
+
+### Pitfall 5: Missing Database Transactions for Multi-Step Operations
+**What goes wrong:** Note created successfully but audit log fails, leaving incomplete audit trail
+**Why it happens:** Controller creates note and logs audit in separate operations without transaction wrapper
+**How to avoid:** Wrap related operations in `DB::transaction()` closure - both succeed or both rollback
+**Warning signs:** Database contains notes without corresponding audit_logs entries
+
+**Source:** [Laravel Daily - Database Transactions: 3 Practical Examples](https://laraveldaily.com/post/laravel-database-transactions-examples)
+
+### Pitfall 6: Storing Full Class Names in notable_type Without Morph Map
+**What goes wrong:** Refactoring model namespace from `App\Models\Member` to `App\Domain\Members\Member` breaks all existing polymorphic relationships
+**Why it happens:** Laravel stores fully qualified class name by default; database contains hardcoded `App\Models\Member` strings
+**How to avoid:** Define morph map in `AppServiceProvider::boot()` using `Relation::enforceMorphMap(['member' => Member::class])` - stores 'member' string instead of class name
+**Warning signs:** After namespace refactor, queries return empty results for previously created polymorphic relations
+
+**Source:** [Laravel 10 Eloquent Relationships - Custom Polymorphic Types](https://laravel.com/docs/10.x/eloquent-relationships)
+
+## Code Examples
+
+Verified patterns from official sources and existing codebase:
+
+### Migration for Notes Table
+```php
+// Source: Laravel 10 migration patterns + existing codebase database/migrations/2026_02_07_120002_create_articles_table.php
+
+id();
+
+ // Polymorphic relationship columns with composite index
+ $table->morphs('notable'); // Creates notable_type, notable_id, and index(['notable_type', 'notable_id'])
+
+ $table->longText('content');
+ $table->foreignId('author_user_id')->constrained('users')->cascadeOnDelete();
+
+ $table->timestamps();
+
+ // Additional index for chronological sorting
+ $table->index('created_at');
+ });
+ }
+
+ public function down(): void
+ {
+ Schema::dropIfExists('notes');
+ }
+};
+```
+
+### Note Model with Polymorphic Relationship
+```php
+// Source: https://laravel.com/docs/10.x/eloquent-relationships + existing codebase patterns
+
+morphTo();
+ }
+
+ /**
+ * Get the user who authored this note
+ */
+ public function author(): BelongsTo
+ {
+ return $this->belongsTo(User::class, 'author_user_id');
+ }
+}
+```
+
+### Member Model with Notes Relationship
+```php
+// Source: Existing codebase app/Models/Member.php pattern
+
+// Add to app/Models/Member.php
+
+use Illuminate\Database\Eloquent\Relations\MorphMany;
+
+class Member extends Model
+{
+ // ... existing code ...
+
+ /**
+ * Get all notes for this member
+ */
+ public function notes(): MorphMany
+ {
+ return $this->morphMany(Note::class, 'notable')->orderBy('created_at', 'desc');
+ }
+}
+```
+
+### Form Request for Note Creation
+```php
+// Source: Existing codebase app/Http/Requests/StoreMemberRequest.php pattern
+
+user()->hasRole('admin')
+ || !$this->user()->getAllPermissions()->isEmpty();
+ }
+
+ public function rules(): array
+ {
+ return [
+ 'content' => 'required|string|min:1|max:65535', // longText column limit
+ ];
+ }
+
+ public function messages(): array
+ {
+ return [
+ 'content.required' => '備忘錄內容為必填欄位',
+ 'content.min' => '備忘錄內容不可為空白',
+ ];
+ }
+}
+```
+
+### Admin Controller for Member Notes
+```php
+// Source: Existing codebase app/Http/Controllers/Admin/ArticleController.php pattern
+
+notes()->create([
+ 'content' => $request->content,
+ 'author_user_id' => $request->user()->id,
+ ]);
+
+ AuditLogger::log('note.created', $note, [
+ 'member_id' => $member->id,
+ 'member_name' => $member->full_name,
+ 'author' => $request->user()->name,
+ ]);
+
+ return $note;
+ });
+
+ return redirect()
+ ->route('admin.members.show', $member)
+ ->with('status', '備忘錄已新增');
+ }
+
+ public function destroy(Member $member, Note $note)
+ {
+ // Verify note belongs to this member (prevent URL manipulation)
+ if ($note->notable_id !== $member->id || $note->notable_type !== Member::class) {
+ abort(404);
+ }
+
+ DB::transaction(function () use ($note, $member) {
+ $note->delete();
+
+ AuditLogger::log('note.deleted', $member, [
+ 'note_id' => $note->id,
+ 'content_preview' => substr($note->content, 0, 50),
+ 'deleted_by' => auth()->user()->name,
+ ]);
+ });
+
+ return redirect()
+ ->route('admin.members.show', $member)
+ ->with('status', '備忘錄已刪除');
+ }
+}
+```
+
+### Preventing N+1 in Member List
+```php
+// Source: Existing codebase app/Http/Controllers/Admin/ArticleCategoryController.php pattern
+
+public function index(Request $request)
+{
+ // withCount adds notes_count via single subquery, preventing N+1
+ $members = Member::withCount('notes')
+ ->orderBy('membership_status')
+ ->orderBy('created_at', 'desc')
+ ->paginate(20);
+
+ return view('admin.members.index', compact('members'));
+}
+```
+
+### Blade View Showing Note Count
+```blade
+
+
+@foreach($members as $member)
+
+ | {{ $member->full_name }} |
+ {{ $member->membership_status_label }} |
+ {{ $member->notes_count }} | {{-- No additional query fired --}}
+
+ 查看
+ |
+
+@endforeach
+```
+
+### Factory for Testing
+```php
+// Source: Existing codebase database/factories/MemberFactory.php pattern
+
+ Member::class,
+ 'notable_id' => Member::factory(),
+ 'content' => $this->faker->paragraph(),
+ 'author_user_id' => User::factory(),
+ ];
+ }
+
+ /**
+ * Indicate that the note belongs to a specific member
+ */
+ public function forMember(Member $member): static
+ {
+ return $this->state(fn () => [
+ 'notable_type' => Member::class,
+ 'notable_id' => $member->id,
+ ]);
+ }
+}
+```
+
+### Feature Test Pattern
+```php
+// Source: Existing codebase tests/Feature/MemberRegistrationTest.php pattern
+
+artisan('db:seed', ['--class' => 'RoleSeeder']);
+ }
+
+ public function test_admin_can_create_note_for_member(): void
+ {
+ $admin = User::factory()->create();
+ $admin->assignRole('admin');
+
+ $member = Member::factory()->create();
+
+ $response = $this->actingAs($admin)
+ ->post(route('admin.members.notes.store', $member), [
+ 'content' => 'Test note content',
+ ]);
+
+ $response->assertRedirect(route('admin.members.show', $member));
+
+ $this->assertDatabaseHas('notes', [
+ 'notable_type' => Member::class,
+ 'notable_id' => $member->id,
+ 'content' => 'Test note content',
+ 'author_user_id' => $admin->id,
+ ]);
+
+ // Verify audit log created
+ $this->assertDatabaseHas('audit_logs', [
+ 'action' => 'note.created',
+ 'auditable_type' => Note::class,
+ ]);
+ }
+
+ public function test_note_count_is_loaded_without_n_plus_1(): void
+ {
+ $admin = User::factory()->create();
+ $admin->assignRole('admin');
+
+ $members = Member::factory()->count(3)->create();
+ foreach ($members as $member) {
+ Note::factory()->count(2)->forMember($member)->create();
+ }
+
+ // Track queries
+ DB::enableQueryLog();
+
+ $this->actingAs($admin)
+ ->get(route('admin.members.index'));
+
+ $queries = DB::getQueryLog();
+
+ // Should be ~2 queries: 1 for members with count subquery, 1 for pagination count
+ $this->assertLessThan(5, count($queries), 'N+1 query detected');
+ }
+}
+```
+
+## State of the Art
+
+| Old Approach | Current Approach | When Changed | Impact |
+|--------------|------------------|--------------|--------|
+| Separate notes tables per entity | Single polymorphic notes table | Laravel 5.0+ (2015) | Reduced schema complexity, easier to add new notable types |
+| Manual composite indexes | `$table->morphs('notable')` helper | Laravel 5.0+ | Automatic index creation, less error-prone |
+| Multiple queries for counts | `withCount()` method | Laravel 5.3 (2016) | Single subquery for all counts, eliminates N+1 |
+| Inline controller validation | Form Request classes | Laravel 5.0+ | Cleaner controllers, reusable validation logic |
+| Manual permission checks | Spatie Laravel Permission package | Package v5+ | Standardized RBAC, role inheritance, caching |
+
+**Deprecated/outdated:**
+- **Separate foreign keys per entity type**: Use polymorphic `notable_type`/`notable_id` instead
+- **`$table->integer('notable_id')->unsigned()`**: Use `$table->unsignedBigInteger()` or let `morphs()` handle it (auto uses bigIncrements)
+- **Manual audit logging to text files**: Use structured database logging with `AuditLogger::log()` for searchability
+
+## Open Questions
+
+1. **Should notes have soft deletes?**
+ - What we know: Existing models like Article use `softDeletes()`, but Member model does not
+ - What's unclear: Business requirement for note recovery vs. hard deletion
+ - Recommendation: Start without soft deletes (simpler), add if business requires note recovery. Can be added later via migration without data loss.
+
+2. **Should notes support file attachments?**
+ - What we know: Requirements mention "text notes" only, existing Article model has separate `article_attachments` table
+ - What's unclear: Future extensibility vs. YAGNI principle
+ - Recommendation: Implement text-only per requirements. If attachments needed later, follow Article pattern with polymorphic `note_attachments` table.
+
+3. **Should notes have access levels (who can view)?**
+ - What we know: Article model has `access_level` (public/members/board/admin), requirements specify "all admin roles can view and write"
+ - What's unclear: Whether different admin roles should have read/write separation
+ - Recommendation: Start with uniform admin access (simpler, matches requirements). If granular permissions needed, add `viewNotes` and `writeNotes` permissions via Spatie package.
+
+4. **Should notable_type use morph map or full class names?**
+ - What we know: Morph map decouples database from class names, but adds configuration overhead
+ - What's unclear: Likelihood of model namespace refactoring in this codebase
+ - Recommendation: Use morph map defensively - add `Relation::enforceMorphMap(['member' => Member::class])` in `AppServiceProvider::boot()`. Low cost, high protection against future refactoring pain.
+
+## Sources
+
+### Primary (HIGH confidence)
+- [Laravel 10.x Eloquent Relationships - Polymorphic](https://laravel.com/docs/10.x/eloquent-relationships) - Official documentation for morphMany/morphTo patterns
+- [Laravel 10.x Form Request Validation](https://laravel.com/docs/10.x/validation) - Official documentation for Form Request classes
+- Existing codebase patterns:
+ - `app/Models/Member.php` - Model structure with constants, relationships
+ - `app/Models/CustomFieldValue.php` - Polymorphic relationship example
+ - `app/Http/Requests/StoreMemberRequest.php` - Form Request validation pattern
+ - `app/Http/Controllers/Admin/ArticleController.php` - Admin controller return patterns
+ - `app/Support/AuditLogger.php` - Audit logging implementation
+ - `database/migrations/2026_02_07_120002_create_articles_table.php` - Modern migration structure
+
+### Secondary (MEDIUM confidence)
+- [Roelof Jan Elsinga - Improve query performance for polymorphic relationships](https://roelofjanelsinga.com/articles/improve-performance-polymorphic-relationships-laravel/) - Composite index performance validation
+- [Yellow Duck - Laravel's Eloquent withCount method](https://www.yellowduck.be/posts/laravels-eloquent-withcount-method) - N+1 prevention with withCount
+- [René Roth - Composite indexes in Laravel & MySQL](https://reneroth.xyz/composite-indices-in-laravel/) - Index column ordering best practices
+- [Laravel Daily - Database Transactions: 3 Practical Examples](https://laraveldaily.com/post/laravel-database-transactions-examples) - Transaction usage patterns
+- [Gergő Tar - Handling API Controllers and JSON Responses](https://gergotar.com/blog/posts/handling-api-controllers-and-json-responses-in-laravel/) - API response patterns (verified admin uses Blade, not JSON)
+
+### Tertiary (LOW confidence)
+- [LogRocket - Polymorphic relationships in Laravel and their use cases](https://blog.logrocket.com/polymorphic-relationships-laravel/) - General conceptual overview
+- [LinkedIn - Implementing and Seeding Polymorphic Relationships](https://www.linkedin.com/pulse/implementing-seeding-polymorphic-relationships-laravel-faizan-kamal-8hutf) - Factory patterns for testing
+
+## Metadata
+
+**Confidence breakdown:**
+- Standard stack: HIGH - Laravel 10.50.0 confirmed via `php artisan --version`, existing patterns verified in codebase
+- Architecture: HIGH - Polymorphic relationships, Form Requests, and admin patterns all verified in existing codebase
+- Pitfalls: HIGH - Composite indexing and N+1 prevention verified in Laravel 10 docs and performance articles from authoritative sources
+- Code examples: HIGH - All examples derived from official Laravel 10 docs or existing codebase patterns
+
+**Research date:** 2026-02-13
+**Valid until:** 2026-03-15 (30 days - Laravel 10 is stable, patterns unlikely to change)