Ticket Planning Examples

BE | Add Google OAuth2 callback endpoint

Classification: type=Story, area=backend, execution_order=foundation, dependency_level=unblocked, target_bucket=next-dev-sprint

**Summary:** Implement the OAuth2 callback action that exchanges the Google authorization code for a user token and creates or finds a User by email.

**Background:** Users need Google login. The callback endpoint completes the OAuth flow after Google redirects back to the app.

**Acceptance Criteria:**
- POST /auth/google/callback exchanges code for token
- Creates or finds User by email from Google profile
- Returns signed session on success; error JSON on failure

**Dependencies:** None. Unblocked.

**Technical Notes:** Uses OAuth2. Callback path must match the redirect URI registered in Google Cloud Console.