feat(leads): add Lead Manager module with full admin and consumer endpoints

- Lead model in admin_api with status/priority/source/assigned_to fields
- Admin API: metrics, list, detail, update views at /api/v1/leads/
- Consumer API: public ScheduleCallView at /api/leads/schedule-call/
- RBAC: 'leads' module registered in ALL_MODULES and StaffProfile scopes
- Migration 0003_lead with indexes on status, priority, created_at, email

admin_api/urls.py

@@ -44,6 +44,12 @@ urlpatterns = [
     path('reviews/<int:pk>/moderate/', views.ReviewModerationView.as_view(), name='review-moderate'),
     path('reviews/<int:pk>/', views.ReviewDeleteView.as_view(), name='review-delete'),
 
+    # Lead Manager
+    path('leads/metrics/', views.LeadMetricsView.as_view(), name='lead-metrics'),
+    path('leads/', views.LeadListView.as_view(), name='lead-list'),
+    path('leads/<int:pk>/', views.LeadDetailView.as_view(), name='lead-detail'),
+    path('leads/<int:pk>/update/', views.LeadUpdateView.as_view(), name='lead-update'),
+
         path('gamification/submit-event/', views.GamificationSubmitEventView.as_view(), name='gamification-submit-event'),
     path('gamification/submit-event', views.GamificationSubmitEventView.as_view()),
     path('shop/items/', views.ShopItemsView.as_view(), name='shop-items'),