Session fixes: auth working, frontend files created, running locally

- Fixed circular imports in API files
- Created missing frontend lib files (api.ts, socket.ts, types.ts)
- Fixed register endpoint to return token instead of user
- Updated Anthropic client version
- Backend running locally on port 8000
- Frontend running on port 3000
- Authentication working
- Still need: channel response fix, WebSocket auth fix

backend/requirements.txt

@@ -29,3 +29,4 @@ minio==7.2.3
 python-jose[cryptography]==3.3.0
 passlib[bcrypt]==1.7.4
 bcrypt==4.1.2
+email-validator