ops(sentry): monitor functional endpoints and background jobs

[guidefari]

Production evidence

Only the one-minute /health uptime check is active. Profile and show checks are disabled. No Sentry Cron monitors cover the reminder loop, hourly sitemap regeneration, or daily database backup.

Acceptance criteria

• Enable production uptime checks for representative profile and show routes.
• Add Sentry Cron check-ins for reminder processing, sitemap regeneration, and database backup.
• Report in-progress, success, and failure outcomes with release/environment correlation.
• Configure missed-check and failure alerts with explicit ownership.
• Verify each monitor receives a successful production check-in.

[linear-code]

OPS-144

[guidefari]

Background-job check-ins are implemented in draft PR #239 for reminder processing, hourly sitemap regeneration, and the daily database backup, including in-progress/ok/error and release/environment correlation. The existing profile/show uptime detectors are correctly configured but disabled; both CLI and authenticated UI return permission errors when enabling them. Keeping this open until an org admin enables those detectors, #239 is deployed, and successful production check-ins are verified.

[guidefari]

Review follow-up in PR #239 commit dbde52f2: the reminder monitor is explicitly tied to the loop tick. The recovery side of the signal race guarantees a tick at least every five minutes even when no reminders are due, so quiet periods still emit check-ins. Backup check-ins now start only beside actual execution, are skipped when Sentry is disabled, and terminal status/flush are awaited. Awaiting deployed monitor check-ins; profile/show uptime enabling remains permission-blocked.

[guidefari]

Post-deploy monitor audit for v2.76.6:

• sitemap-regeneration: active in production, status OK, latest successful check-in at 2026-07-30 23:57:07 UTC.
• reminder-processing: monitor exists but is disabled and has no production environment/check-in.
• Database backup: no verified production check-in yet.
• Representative profile/show uptime detectors remain disabled because Sentry rejects enablement with the current permissions.

Keeping this open until each required monitor has a successful production check-in and the functional uptime detectors/ownership are active.