Add privacy-friendly analytics and cookie consent, integrated into the CMS

Adds a first-party analytics system with no third-party trackers and no
persistent per-visitor identifiers: events are grouped into sessions via a
daily-rotating pseudonymous hash (IP+UA+host, HMAC-salted, never stored raw).

- New "Analytics" section in the Payload admin, gated by a canViewAnalytics
  permission on Users, following the existing custom-admin-view pattern
  used by the calendar feature
- Sessions, page views, unique visitors, top/entry/exit pages, events,
  device/browser breakdown, date range filter with period comparison
- Raw events and daily aggregate rollups as their own collections, with
  configurable retention and a cron endpoint that rolls up before purging
- Cookie consent banner (necessary/preferences/statistics) with categories
  and copy editable from a new CMS global; a track() helper that is a
  complete no-op without statistics consent, so nothing is ever sent
  before a visitor opts in
- track() calls wired into the booking flow, contact form, and navigation

package.json

@@ -30,6 +30,7 @@
     "payload": "^3.88.0",
     "react": "19.2.8",
     "react-dom": "19.2.8",
+    "recharts": "^3.10.1",
     "sharp": "^0.35.3",
     "tsx": "^4.23.12",
     "ws": "^8.21.3"