NOTIFICATION_ADMIN_EMAILS made "add Beto to the summaries" a redeploy — the wrong unit of work for a list that changes when office staff change. Adds `app_settings`, a key/value table for the configuration staff must be able to change without a deploy, and `SettingsService`, which resolves every key db -> env -> default and reports which of the three a value came from. That ladder is what makes the move safe: a deployment behaves exactly as before until somebody saves in the UI, and the screen can say "this is still coming from the deployment" rather than implying somebody chose it. - new ability `setting:manage` (ADMIN) — deliberately above `notification:send`, since redirecting the audit summaries is how someone would quietly stop them being read - GET/PUT /notifications/settings/admin-emails; read is open to any logged-in user so the UI can display the list, write is gated - resolved per job, not cached at boot, or we would reintroduce exactly the restart-to-apply behaviour being removed - a saved empty list means "nobody" and does NOT fall through to the env, or clearing the field would keep mailing the people just removed Credentials stay in env — see the model doc for where the line is drawn. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>