fix(auth): fix auth module bugs, add transactions, clean up scrap code

[ayeshakhalid192007-dev]

Summary

• Fixed auth module bugs: added null check for restaurant relation during login, wrapped admin registration in a database transaction for atomicity
• Cleaned up codebase: removed duplicate harouns-ux/ and unused scrap-menu/ modules, registered all feature modules in AppModule with rate limiting (ThrottlerModule)
• Fixed frontend issues: corrected admin-registration route typo, updated API client

Test plan

• Verify admin login works when restaurant relation is missing (should return proper error)
• Verify admin registration creates both restaurant and admin atomically
• Verify rate limiting is active on API endpoints
• Verify frontend login and admin registration pages work correctly

🤖 Generated with Claude Code

[ayeshakhalid192007-dev]

Fixed auth module bugs — added a null check for the restaurant relation during login and wrapped admin registration in a database transaction to ensure atomicity. Cleaned up the codebase by removing duplicate harouns-ux/ and unused scrap-menu/ modules, and registered all feature modules in AppModule with rate limiting via ThrottlerModule. Fixed frontend issues — corrected the admin-registration route typo and updated the API client.