feat: notifications, audit logging, and admin improvements

- Add centralized notification service with webhook (Discord/Slack) and
  email (SMTP) support, triggered for trip invites, booking changes,
  collab messages, and trip reminders
- Webhook sends one message per event (group channel); email sends
  individually per trip member, excluding the actor
- Discord invite notifications now include the invited user's name
- Add LOG_LEVEL env var (info/debug) controlling console and file output
- INFO logs show user email, action, and IP for audit events; errors
  for HTTP requests
- DEBUG logs show every request with full body/query (passwords redacted),
  audit details, notification params, and webhook payloads
- Add persistent trek.log file logging with 10MB rotation (5 files)
  in /app/data/logs/
- Color-coded log levels in Docker console output
- Timestamps without timezone name (user sets TZ via Docker)
- Add Test Webhook and Save buttons to admin notification settings
- Move notification event toggles to admin panel
- Add daily trip reminder scheduler (9 AM, timezone-aware)
- Wire up booking create/update/delete and collab message notifications
- Add i18n keys for notification UI across all 13 languages

Made-with: Cursor

server/src/routes/collab.ts

@@ -126,6 +126,11 @@ router.post('/notes', authenticate, (req: Request, res: Response) => {
   const formatted = formatNote(note);
   res.status(201).json({ note: formatted });
   broadcast(tripId, 'collab:note:created', { note: formatted }, req.headers['x-socket-id'] as string);
+
+  import('../services/notifications').then(({ notifyTripMembers }) => {
+    const tripInfo = db.prepare('SELECT title FROM trips WHERE id = ?').get(tripId) as { title: string } | undefined;
+    notifyTripMembers(Number(tripId), authReq.user.id, 'collab_message', { trip: tripInfo?.title || 'Untitled', actor: authReq.user.username }).catch(() => {});
+  });
 });
 
 router.put('/notes/:id', authenticate, (req: Request, res: Response) => {