feat(v2): add multiple extra features from the pdf slides

backend/processing/selectors.py

@@ -1,4 +1,4 @@
-from .models import ImageSession, ProcessingJob
+from .models import ImageSession, ImageState, ProcessingJob
 
 
 def image_session_get(*, session_id):
@@ -7,3 +7,11 @@ def image_session_get(*, session_id):
 
 def processing_job_get(*, job_id):
     return ProcessingJob.objects.filter(id=job_id).first()
+
+
+def image_state_get(*, state_id):
+    return ImageState.objects.select_related("session", "parent").filter(id=state_id).first()
+
+
+def image_states_list(*, session_id):
+    return ImageState.objects.select_related("parent").filter(session_id=session_id).order_by("sequence", "created_at")