Fix bundle analyzer to use webpack instead of Turbopack

Bundle analyzer requires webpack, add --webpack flag to build:analyze script.

Note: This makes analysis builds slower but enables bundle visualization.
Regular builds still use faster Turbopack.

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

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

package.json

@@ -7,7 +7,7 @@
     "dev": "concurrently \"contentlayer2 dev\" \"next dev --turbo\"",
     "sync-assets": "node scripts/sync-assets.mjs",
     "build": "npm run sync-assets && contentlayer2 build && next build && npx pagefind --site .next && rm -rf public/_pagefind && cp -r .next/pagefind public/_pagefind",
-    "build:analyze": "ANALYZE=true npm run build",
+    "build:analyze": "npm run sync-assets && contentlayer2 build && ANALYZE=true next build --webpack",
     "start": "next start",
     "lint": "next lint",
     "contentlayer": "contentlayer build"