First-run setup wizard

Crumb's biggest install-time hurdle was always the same: knowing which env vars to set and in what order. The new first-run setup wizard at /admin walks through it.

The steps

1. Create your administrator. Username and password.
2. Server address. The reachable URL native clients should connect to.
3. Storage. Confirm or change the media root.
4. First camera. Name + RTSP URL, optionally MJPEG snapshot.
5. Frigate (optional). MQTT broker URL + per-camera Frigate name.
6. Done. You're recording.

Implementation notes

• Migration 0027 adds the wizard state column
• /auth/setup-status is Host-derived so the wizard prefills the server URL
• backfill=true so existing admin installs don't suddenly see the wizard;

it only shows for fresh databases, or when you click Run setup again in Settings

Deployed to the crumbvms production stack (API container). Committed in 4e8785d. See also: the AI-assisted install runbook.