Implement asset upload API and utility functions

- Add Asset and CardLayer model updates
- Create asset upload API endpoints
- Add AssetUploadDialog component
- Create card layout algorithms
- Implement symmetry generation utils
- Add template configurations

backend/apps/projects/urls.py

@@ -1,7 +1,9 @@
 from django.urls import path
-from .views import project_list, project_detail
+from .views import project_list, project_detail, asset_list, asset_detail
 
 urlpatterns = [
     path('', project_list, name='project-list'),
     path('<str:pk>/', project_detail, name='project-detail'),
+    path('<str:project_pk>/assets/', asset_list, name='asset-list'),
+    path('<str:project_pk>/assets/<str:asset_pk>/', asset_detail, name='asset-detail'),
 ]