refactor(auth): remove legacy RESTful user routes and migrate authentication to GraphQL context

- Rename get_current_user to get_current_user_id in auth/deps.py to clarify intent
- Remove legacy /me, /logout routes, and placeholder function from auth/__init__.py
- Remove dependency_overrides from app/main.py
- Update CustomContext to resolve and cache full User objects via db query

auth/oauth/google.py

@@ -9,7 +9,6 @@ import json
 from urllib.parse import quote
 from dotenv import load_dotenv
 
-from auth.deps import get_current_user
 from app.db import SessionLocal
 from app.models import User
 from auth.tokens import create_jwt_token, create_refresh_token, decode_token
@@ -213,29 +212,4 @@ async def auth_callback(request: Request, code: str, state: str, background_task
     
     response.delete_cookie("oauth_state")
     
-    return response
-
-# @router.get("/me")
-# def me(user = Depends(get_current_user)):
-#     return {
-#         "email": user.email,
-#         "name": user.name,
-#         "avatar": get_image_url(user.avatar),
-#     }
-    
-# @router.post("/refresh")
-# def refresh_token(refresh_token: str):
-#     payload = decode_token(refresh_token)
-
-#     if payload.get("type") != "refresh":
-#         raise HTTPException(status_code=401)
-
-#     user_id = payload.get("sub")
-
-#     new_access = create_jwt_token({"sub": user_id})
-
-#     return {"access_token": new_access}
-
-# @router.post("/logout")
-# def logout():
-#     return {"message": "ok"}
+    return response