PM2 cluster deploy + Redis caching + Nginx gzip + UI polish

- PM2 v6: 2x API cluster + 1x web, zero-downtime reload
- Redis cache: 30s TTL on GET /tasks, X-Cache header
- Nginx gzip compression
- Mobile touch targets 44px
- Czech diacritics throughout UI
- TaskModal slide-up animation
- StatusBadge color dots
- GroupSelector emoji icons

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/tasks/package.json

@@ -15,7 +15,8 @@
     "@fullcalendar/timegrid": "^6.1.20",
     "next": "14.2.35",
     "react": "^18",
-    "react-dom": "^18"
+    "react-dom": "^18",
+    "react-swipeable": "^7.0.2"
   },
   "devDependencies": {
     "@types/node": "^20",