feat: Add photo galleries to services, resource types management, and UI improvements

Major features:
- Add drag-and-drop photo gallery to Service create/edit modals
- Add Resource Types management section to Settings (CRUD for custom types)
- Add edit icon consistency to Resources table (pencil icon in actions)
- Improve Services page with drag-to-reorder and customer preview mockup

Backend changes:
- Add photos JSONField to Service model with migration
- Add ResourceType model with category (STAFF/OTHER), description fields
- Add ResourceTypeViewSet with CRUD operations
- Add service reorder endpoint for display order

Frontend changes:
- Services page: two-column layout, drag-reorder, photo upload
- Settings page: Resource Types tab with full CRUD modal
- Resources page: Edit icon in actions column instead of row click
- Sidebar: Payments link visibility based on role and paymentsEnabled
- Update types.ts with Service.photos and ResourceTypeDefinition

Note: Removed photos from ResourceType (kept only for Service)

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

frontend/src/pages/Customers.tsx

@@ -99,7 +99,8 @@ const Customers: React.FC<CustomersProps> = ({ onMasquerade, effectiveUser }) =>
     return sorted;
   }, [customers, searchTerm, sortConfig]);
   
-  const canMasquerade = ['owner', 'manager', 'staff'].includes(effectiveUser.role);
+  // Only owners can masquerade as customers (per backend permissions)
+  const canMasquerade = effectiveUser.role === 'owner';
 
   if (isLoading) {
     return (