Microsoft 365 OAuth not configured yet

Set MS_OAUTH_CLIENT_ID + MS_OAUTH_CLIENT_SECRET env vars on Beast.

Steps to set up:

1. Visit Microsoft Entra → App registrations
2. Register new app → Web platform
3. Redirect URI: https://mmm-app.srv1558001.hstgr.cloud/oauth-callback.php
4. API permissions: Mail.ReadWrite, Mail.Send, Calendars.ReadWrite, offline_access
5. Create client secret → copy ID + secret → drop in chat