feat: Add Spectacutlar API schema generation

src/fellchensammlung/urls.py

@@ -5,6 +5,7 @@ from .forms import CustomRegistrationForm
 from .feeds import LatestAdoptionNoticesFeed
 
 from . import views
+from drf_spectacular.views import SpectacularAPIView, SpectacularRedocView, SpectacularSwaggerView
 
 urlpatterns = [
     path("", views.index, name="index"),
@@ -82,6 +83,10 @@ urlpatterns = [
     ## API ##
     #########
     path('api/', include('fellchensammlung.api.urls')),
+    path('api/schema/', SpectacularAPIView.as_view(), name='schema'),
+    # Optional UI:
+    path('api/schema/swagger-ui/', SpectacularSwaggerView.as_view(url_name='schema'), name='swagger-ui'),
+    path('api/schema/redoc/', SpectacularRedocView.as_view(url_name='schema'), name='redoc'),
 
     ###################
     ## External Site ##