fix: improve skill category syncing and data structure

- Enhanced skill category syncing by ensuring id and name properties are included, boosting data integrity.
- Cleaned up admin exports related to skill categories for better maintainability.

.cursor/rules/project-structure.mdc

@@ -0,0 +1,30 @@
+---
+alwaysApply: true
+---
+
+# Project Structure Rules
+
+1. Backend:
+   - [services/](mdc:services/) - ALL database access
+   - [app/api/](mdc:app/api/) - API routes using services
+
+2. Frontend:
+   - [clients/](mdc:clients/) - HTTP clients
+   - [components/](mdc:components/) - React components
+   - [hooks/](mdc:hooks/) - React hooks
+
+3. Shared:
+   - [lib/](mdc:lib/) - Types and utilities
+   - [scripts/](mdc:scripts/) - Utility scripts
+
+Key Files:
+
+- [services/database.ts](mdc:services/database.ts) - Database pool
+- [clients/base/http-client.ts](mdc:clients/base/http-client.ts) - Base HTTP client
+- [lib/types.ts](mdc:lib/types.ts) - Shared types
+
+❌ FORBIDDEN:
+
+- Database access outside services/
+- HTTP calls outside clients/
+- Business logic in components/