Fix skeleton entry deletion and add hide suggestions toggle (#619)

- Revert filled skeleton entries back to skeleton on delete instead of permanently removing them
- Add per-user hide_skeletons preference on journey_contributors (migration 99)
- Add PATCH /journeys/:id/preferences endpoint for toggling skeleton visibility
- Add Eye/EyeOff toggle button with custom tooltip in journey detail header
- Filter skeleton entries from timeline when hidden
- Add i18n keys for all 14 languages

server/src/routes/journey.ts

@@ -279,6 +279,15 @@ router.delete('/:id/contributors/:userId', authenticate, (req: Request, res: Res
   res.json({ success: true });
 });
 
+// ── User Preferences ─────────────────────────────────────────────────────
+
+router.patch('/:id/preferences', authenticate, (req: Request, res: Response) => {
+  const authReq = req as AuthRequest;
+  const result = svc.updateJourneyPreferences(Number(req.params.id), authReq.user.id, req.body);
+  if (!result) return res.status(403).json({ error: 'Not allowed' });
+  res.json(result);
+});
+
 // ── Share Link ────────────────────────────────────────────────────────────
 
 router.get('/:id/share-link', authenticate, (req: Request, res: Response) => {