Add @extend_schema decorators to moderation ViewSet actions

- Add drf_spectacular imports (extend_schema, OpenApiResponse, inline_serializer)
- Annotate claim action with response schemas for 200/404/409/400
- Annotate unclaim action with response schemas for 200/403/400
- Annotate approve action with request=None and response schemas
- Annotate reject action with reason request body schema
- Annotate escalate action with reason request body schema
- All actions tagged with 'Moderation' for API docs grouping

backend/apps/moderation/services.py

@@ -13,7 +13,7 @@ from django_fsm import TransitionNotAllowed
 
 from apps.accounts.models import User
 
-from .models import EditSubmission, ModerationQueue, PhotoSubmission
+from .models import EditSubmission, ModerationQueue
 
 
 class ModerationService:
@@ -444,9 +444,9 @@ class ModerationService:
         return queue_item
 
     @staticmethod
-    def _create_queue_item_for_photo_submission(*, submission: PhotoSubmission, submitter: User) -> ModerationQueue:
+    def _create_queue_item_for_photo_submission(*, submission: EditSubmission, submitter: User) -> ModerationQueue:
         """
-        Create a moderation queue item for a photo submission.
+        Create a moderation queue item for a photo submission (EditSubmission with type=PHOTO).
 
         Args:
             submission: The photo submission
@@ -587,8 +587,9 @@ class ModerationService:
                     raise ValueError(f"Unknown action: {action}")
 
             elif "photo_submission" in queue_item.tags:
-                # Find PhotoSubmission
-                submissions = PhotoSubmission.objects.filter(
+                # Find PHOTO EditSubmission
+                submissions = EditSubmission.objects.filter(
+                    submission_type="PHOTO",
                     user=queue_item.flagged_by,
                     content_type=queue_item.content_type,
                     object_id=queue_item.entity_id,