Handle multiple images shared in query to chat API

Previously Khoj could respond to a single shared image at a time.

This changes updates the chat API to accept multiple images shared by
the user and send it to the appropriate chat actors including the
openai response generation chat actor for getting an image aware
response

src/khoj/processor/image/generate.py

@@ -26,7 +26,7 @@ async def text_to_image(
     references: List[Dict[str, Any]],
     online_results: Dict[str, Any],
     send_status_func: Optional[Callable] = None,
-    uploaded_image_url: Optional[str] = None,
+    query_images: Optional[List[str]] = None,
     agent: Agent = None,
 ):
     status_code = 200
@@ -65,7 +65,7 @@ async def text_to_image(
         note_references=references,
         online_results=online_results,
         model_type=text_to_image_config.model_type,
-        uploaded_image_url=uploaded_image_url,
+        query_images=query_images,
         user=user,
         agent=agent,
     )