- Call _build_google_auth() at module level before mcp = FastMCP(...)
- Pass auth=_google_auth to FastMCP() constructor
- Add startup log in run_server(): INFO when OAuth enabled (with redirect URI), WARNING when open/unauthenticated
- Add test verifying mcp has no auth provider when Google vars are absent (baseline + post-wire)
Adds _build_google_auth() to server.py that reads Google OAuth settings
and returns a configured GoogleProvider instance or None when unconfigured.
Includes warning for stdio transport incompatibility and conditional
jwt_signing_key passthrough. 4 new TDD tests in tests/test_auth_builder.py.