Updates API

Method	Path	Purpose
`GET`	`/api/v1/updates/status`	Current version + channel
`GET`	`/api/v1/updates/check`	Compare to upstream
`POST`	`/api/v1/updates/apply`	Download + migrate + restart (admin)
`POST`	`/api/v1/updates/channel`	`{ "channel": "stable" \| "beta" }`

⚠️ Warning: Beta channel may ship database migrations — take a backup first.

Troubleshooting

502 during apply
Mirror reboot mid-flight — re-run apply after SSH recovery; core should be idempotent.