Add membership fee system with disability discount and fix document permissions

Features:
- Implement two fee types: entrance fee and annual fee (both NT$1,000)
- Add 50% discount for disability certificate holders
- Add disability certificate upload in member profile
- Integrate disability verification into cashier approval workflow
- Add membership fee settings in system admin

Document permissions:
- Fix hard-coded role logic in Document model
- Use permission-based authorization instead of role checks

Additional features:
- Add announcements, general ledger, and trial balance modules
- Add income management and accounting entries
- Add comprehensive test suite with factories
- Update UI translations to Traditional Chinese

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

resources/views/auth/register.blade.php

@@ -40,7 +40,7 @@
         </div>
 
         <div class="flex items-center justify-end mt-4">
-            <a class="underline text-sm text-gray-600 hover:text-gray-900 rounded-md focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-indigo-500" href="{{ route('login') }}">
+            <a class="underline text-sm text-gray-600 dark:text-gray-400 hover:text-gray-900 dark:hover:text-gray-100 rounded-md focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-indigo-500 dark:focus:ring-offset-gray-800" href="{{ route('login') }}">
                 {{ __('Already registered?') }}
             </a>