feat: implement dashboard ban overview (Stage 5)

- Add ban_service reading fail2ban SQLite DB via read-only aiosqlite
- Add geo_service resolving IPs via ip-api.com with 10k in-memory cache
- Add GET /api/dashboard/bans and GET /api/dashboard/accesses endpoints
- Add TimeRange, DashboardBanItem, DashboardBanListResponse, AccessListItem,
  AccessListResponse models in models/ban.py
- Build BanTable component (Fluent UI DataGrid) with bans/accesses modes,
  pagination, loading/error/empty states, and ban-count badges
- Build useBans hook managing time-range and pagination state
- Update DashboardPage: status bar + time-range toolbar + tab switcher
- Add 37 new backend tests (ban service, geo service, dashboard router)
- All 141 tests pass; ruff/mypy --strict/tsc --noEmit clean

frontend/package.json

@@ -30,8 +30,10 @@
     "eslint": "^9.13.0",
     "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-react-hooks": "^5.0.0",
+    "jiti": "^2.6.1",
     "prettier": "^3.3.3",
     "typescript": "^5.6.3",
+    "typescript-eslint": "^8.56.1",
     "vite": "^5.4.11"
   }
 }