OAuth Callback — Waiting for Web Client

This service is up, but the Web OAuth client is not configured yet.

Google only accepts https redirect URIs on "Web application" OAuth clients. The current client is installed type (localhost-only) — exactly why sign-in dead-ends.

One-time console step (5 min, David):

1. Open console.cloud.google.com/apis/credentials (project ihe-crm-507220).
2. Create Credentials → OAuth client ID → Web application — name Tia Web.
3. Authorized redirect URIs: https://oauth.tiaproject.tech/oauth-callback.
4. Copy the Client ID + Secret into /opt/shared-workspace/gmail-auth/client_secret_web.json (start from the .template file).
5. Reload this page — the button appears.

Full walkthrough: /opt/shared-workspace/gmail-auth/OAUTH-WEB-CLIENT-WALKTHROUGH.md