feat: production readiness — security, perf, bug fixes, bridge self-monitoring

Comprehensive multi-area pass driven by a parallel 8-agent production
review. Frontend, backend, database, security, performance, operational,
plus a new self-monitoring feature.

## Critical fixes
- Planka webhook: reads bounded raw body (was NameError on every call)
- HA quiet hours: ha_state_changed/automation_triggered/service_called/
  event_fired added to deferrable set (were silently dropped)
- DNS-rebinding SSRF: PinnedResolver wired into shared aiohttp session
- Telegram inbound webhook: secret now mandatory (401 without)
- Generic webhook: auth_mode="none" requires explicit
  acknowledge_unauthenticated=true; per-IP rate limit 60/min
- svelte-check: 5 null-narrowing errors in EventDetailModal fixed
- Provider hardcoding: Immich-only block extracted to descriptor
  featureDiscoveryHint
- command_sync: snapshot+expunge bot before exiting AsyncSession

## Bug fixes
- notifier asyncio.gather(return_exceptions=True) — one bad chat no longer
  cancels peer sends
- NotificationDispatcher hoisted out of per-tracker loop
- Provider credential resolution unified across all 5 dispatch sites
- HA asyncio.shield now drains inner task on cancellation
- Provider construction switched from if/elif ladder to factory registry
- NUT first poll seeds silently (no spurious ups_on_battery)
- Quiet-hours gate: event-type-disabled now wins over deferral
- APScheduler drain job ID resolution upgraded to seconds
- HA on_status_change wired through to EventLog
- Webhook payload rollback failures now logged (not swallowed)
- Batched receivers/chats/bots in load_link_data (was per-target N+1)
- flag_modified on JSON column reassignments in deferred_dispatch

## Database
- UNIQUE indexes on service_provider.webhook_token,
  telegram_bot.webhook_path_id, partial UNIQUE on telegram_bot.bot_id,
  telegram_chat(bot_id, chat_id), notification_tracker_target unique link,
  partial UNIQUE on bridge_self provider per user
- Composite ix_event_log_user_event_type_created index
- save_chat_from_webhook switched to ON CONFLICT DO UPDATE
- ondelete=CASCADE on user-id FKs (model annotation; app-side cascade
  delete added for existing data)
- delete_notification_tracker converted from N+1 to bulk DELETE/UPDATE
- Module-level asyncio.Lock replaced with lazy _get_lock() pattern
- VACUUM INTO snapshot now PRAGMA integrity_check verified

## Performance
- Jinja2 template compilation LRU cached (lru_cache maxsize=512)
- Per-locale render cache in NotificationDispatcher (skips re-rendering
  identical content for receivers sharing a locale)
- Tracker list cached per provider_id with 5s TTL + explicit invalidation
  on tracker CRUD (relieves HA chat-bus rate query pressure)
- Nav-counts collapsed from 16 round-trips to single UNION ALL
- HA event_log: skip persisting empty assets_added/removed events

## Security hardening
- Mass-assignment guard on Action create/update; cron sub-minute reject
- Backup JSON depth/node-count cap (depth ≤ 10, nodes ≤ 100k)
- _sanitize_config extended to all JSON-typed fields on backup import
- Telegram _safe_get walks redirects manually with SSRF revalidation
- Bcrypt 72-byte password length cap with clear 422
- Webhook payload body redaction; sensitive substring set extended with
  oauth/client_secret/webhook_secret/csrf in both header filter and
  template extras filter

## Frontend
- 76 catch (err: any) sites converted to errMsg(err) helper
- globalProviderFilter: pure getter; reconciliation moved to one-time
  $effect in +layout
- Provider-filter binding: removed paired $effects + _syncingFilter flag,
  now one-way derived
- entity-cache: separate _refreshing flag for background re-fetches
- api.ts 401 handling: AuthRedirectError class + dedup _redirecting flag,
  goto() instead of window.location.href
- a11y: aria-expanded on mobile More, role=switch + aria-checked on
  Telegram bot toggles

## Tests & operations
- CI pytest gate added to .gitea/workflows/build.yml + release.yml
  (wheel-built install to dodge editable-install slowness)
- /api/ready upgraded to deep healthcheck (db SELECT 1, scheduler.running,
  HA supervisor presence) returning {ready, checks, errors, version}
- /api/metrics endpoint with prometheus_client (deferred_pending,
  event_log_total, dispatch_duration, poll_failures, send_failures)
- New OPERATIONS.md covering deploy, healthchecks, metrics, backup/restore
  procedures, log handling, common scenarios, upgrade flow
- New tests: test_bridge_self (11), test_gitea_parser (9),
  test_planka_parser (6), test_immich_change_detector (6),
  test_backup_roundtrip (1)

## New feature: bridge self-monitoring
- New bridge_self provider type — internal sink for bridge health events
- Three event types: bridge_self_poll_failures (consecutive tracker poll
  failures), bridge_self_deferred_backlog (pending count crosses
  threshold), bridge_self_target_failures (consecutive 5xx/network
  failures per target)
- Per-user thresholds (defaults: 3 / 100 / 5) configurable via the
  provider config form
- Auto-seeded on user create + /setup + boot backfill for existing users
- Anti-spam: counters reset after emission; backlog uses transition latch
- Self-loop guard: bridge_self failures don't count toward target-failure
  thresholds (logged only) — wire to your own Telegram/Email/Matrix to
  get notified when polls/dispatches/sends fail
- 6 default templates (3 events × 2 locales), tracking config columns
  with backfill migration, frontend descriptor (excluded from "create
  provider" wizard since auto-managed)

Operator-visible behavior changes (call out in release notes):
- NOTIFY_BRIDGE_TELEGRAM_WEBHOOK_SECRET now REQUIRED for webhook mode
- Existing webhook providers with auth_mode="none" need explicit opt-in
- Generic webhook endpoint rate-limited 60/min per source IP
- HA disconnect/reconnect writes ha_status_* EventLog rows
- Every user gets a bridge_self provider — wire it to a target to
  receive failure alerts

Pre-existing test failures (test_ssrf, test_release_provider) on
Python 3.13 are unrelated; CI runs on 3.12.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/routes/notification-trackers/TrackerForm.svelte

@@ -59,9 +59,36 @@
 	}: Props = $props();
 
 	let descriptor = $derived(getDescriptor(providerType));
-	let isScheduler = $derived(providerType === 'scheduler');
-	let isWebhook = $derived(descriptor?.webhookBased ?? false);
 	let colMeta = $derived(descriptor?.collectionMeta);
+	// Providers without a collection (currently just the scheduler) drive the
+	// scheduler-specific form layout. Reading from the descriptor keeps the
+	// branch out of the component and lets a future provider opt in by
+	// declaring `collectionMeta: null`.
+	let isScheduler = $derived(colMeta == null);
+	let isWebhook = $derived(descriptor?.webhookBased ?? false);
+
+	/**
+	 * Resolve `{tracking_config_id}` / `{template_config_id}` placeholders in a
+	 * descriptor-declared CTA href. When the corresponding form field is unset
+	 * (value 0), strip the entire `?edit=...` query so the link still goes to
+	 * the list page. Centralising this here avoids per-provider href logic
+	 * leaking back into the template.
+	 */
+	function resolveHintHref(href: string): string {
+		const tcId = form.default_tracking_config_id;
+		const tplId = form.default_template_config_id;
+		if (href.includes('{tracking_config_id}')) {
+			return tcId
+				? href.replace('{tracking_config_id}', String(tcId))
+				: href.split('?')[0];
+		}
+		if (href.includes('{template_config_id}')) {
+			return tplId
+				? href.replace('{template_config_id}', String(tplId))
+				: href.split('?')[0];
+		}
+		return href;
+	}
 
 	// Custom variable management for scheduler
 	function addVariable() {
@@ -231,29 +258,27 @@
 		{/if}
 
 		<!-- Feature discovery: the periodic/scheduled/memory/quiet-hours controls
-		     live on the tracking config, not on the tracker itself. Surface this
-		     here so users don't have to stumble onto the feature by reading docs. -->
-		{#if providerType === 'immich'}
+		     live on the tracking config, not on the tracker itself. The hint
+		     content (message + CTAs) is declared on the provider descriptor so
+		     each provider can surface its own discoverability links without
+		     embedding `if (type === 'xyz')` here. -->
+		{#if descriptor?.featureDiscoveryHint}
+		{@const hint = descriptor.featureDiscoveryHint}
 		<div class="flex items-start gap-2 rounded-md border border-[var(--color-border)] bg-[var(--color-muted)]/30 px-3 py-2">
 			<span style="color: var(--color-primary);"><MdiIcon name="mdiInformationOutline" size={16} /></span>
 			<div class="flex-1 text-xs">
-				<p style="color: var(--color-muted-foreground);">{t('notificationTracker.featureDiscovery')}</p>
-				<div class="flex flex-wrap gap-x-4 gap-y-1 mt-1">
-					<a href={form.default_tracking_config_id
-						? `/tracking-configs?edit=${form.default_tracking_config_id}`
-						: '/tracking-configs'}
-						class="inline-flex items-center gap-1 text-[var(--color-primary)] hover:underline">
-						<MdiIcon name="mdiArrowRight" size={12} />
-						{t('notificationTracker.openTrackingConfig')}
-					</a>
-					<a href={form.default_template_config_id
-						? `/template-configs?edit=${form.default_template_config_id}`
-						: '/template-configs'}
-						class="inline-flex items-center gap-1 text-[var(--color-primary)] hover:underline">
-						<MdiIcon name="mdiArrowRight" size={12} />
-						{t('notificationTracker.openTemplateConfig')}
-					</a>
-				</div>
+				<p style="color: var(--color-muted-foreground);">{t(hint.messageKey)}</p>
+				{#if hint.ctas && hint.ctas.length > 0}
+					<div class="flex flex-wrap gap-x-4 gap-y-1 mt-1">
+						{#each hint.ctas as cta}
+							<a href={resolveHintHref(cta.href)}
+								class="inline-flex items-center gap-1 text-[var(--color-primary)] hover:underline">
+								<MdiIcon name={cta.icon ?? 'mdiArrowRight'} size={12} />
+								{t(cta.labelKey)}
+							</a>
+						{/each}
+					</div>
+				{/if}
 			</div>
 		</div>
 		{/if}