feat: complete UI/UX overhaul - dashboard unification, calendar UX, mobile optimization

- Dashboard redesign as command center with filters, quick actions, inline approve/reject
- Reusable components: BookingRow, BookingFilters, ActionMenu, BookingPreviewModal, BookingEditModal
- Calendar: drag & drop reschedule, eventClick preview modal, grid/list toggle
- Mobile: segmented control bookings/calendar toggle, compact pills, responsive layout
- Collapsible filters with active count badge
- Smart menu positioning with Teleport
- Calendar/list bidirectional data sync
- Navigation: unified History page, removed AdminPending
- Google Calendar OAuth integration
- Dark mode contrast improvements, breadcrumb navigation
- useLocalStorage composable for state persistence

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/package-lock.json

@@ -11,6 +11,7 @@
         "@fullcalendar/core": "^6.1.0",
         "@fullcalendar/daygrid": "^6.1.0",
         "@fullcalendar/interaction": "^6.1.0",
+        "@fullcalendar/list": "^6.1.20",
         "@fullcalendar/timegrid": "^6.1.0",
         "@fullcalendar/vue3": "^6.1.0",
         "axios": "^1.6.0",
@@ -582,6 +583,15 @@
         "@fullcalendar/core": "~6.1.20"
       }
     },
+    "node_modules/@fullcalendar/list": {
+      "version": "6.1.20",
+      "resolved": "https://registry.npmjs.org/@fullcalendar/list/-/list-6.1.20.tgz",
+      "integrity": "sha512-7Hzkbb7uuSqrXwTyD0Ld/7SwWNxPD6SlU548vtkIpH55rZ4qquwtwYdMPgorHos5OynHA4OUrZNcH51CjrCf2g==",
+      "license": "MIT",
+      "peerDependencies": {
+        "@fullcalendar/core": "~6.1.20"
+      }
+    },
     "node_modules/@fullcalendar/timegrid": {
       "version": "6.1.20",
       "resolved": "https://registry.npmjs.org/@fullcalendar/timegrid/-/timegrid-6.1.20.tgz",