Add drag-and-drop reordering to categories page

- Replace up/down chevron buttons with @dnd-kit drag handles
- Update pack generation and question review commands
- Fix MCP bridge and add supabase package.json for Docker

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

apps/admin/package.json

@@ -10,6 +10,9 @@
         "preview": "vite preview"
     },
     "dependencies": {
+        "@dnd-kit/core": "^6.3.1",
+        "@dnd-kit/sortable": "^10.0.0",
+        "@dnd-kit/utilities": "^3.2.2",
         "@emoji-mart/data": "^1.2.1",
         "@emoji-mart/react": "^1.1.1",
         "@radix-ui/react-avatar": "^1.0.4",