feat: init Analytics panel

[666mxvbee]

This PR adds the first full version of the Analytics section to the admin panel.

Implemented:

• Added /analytics route and sidebar navigation entry.
• Added frontend analytics API client for /admin/analytics/* contracts.
• Added analytics access logic for admins and partner users.
• Built the main analytics dashboard with:
  • period, zone, camera, granularity filters;
  • auto-refresh;
  • KPI cards;
  • Yandex map with cameras and zones;
  • occupancy history chart;
  • occupancy forecast chart;
  • observations rate chart;
  • model confidence chart;
  • detector health table.
• Added zone analytics detail view.
• Added camera analytics detail view with snapshots, charts, zone health, and recent detections.
• Added detection run detail view with raw/annotated image comparison.
• Added detection quality feedback form.
• Added admin-only feedback history block.
• Added VITE_ANALYTICS_STALE_MINUTES to .env.example.
  Notes:
  Analytics blocks handle loading, empty, and error states independently.
  If one analytics endpoint fails, the rest of the page remains usable.
  Some data rendering depends on backend availability for the new analytics endpoints.

[666mxvbee]

do not push still in test