Add Vision Support (#889)

# Summary of Changes
* New UI to show preview of image uploads
* ChatML message changes to support gpt-4o vision based responses on images
* AWS S3 image uploads for persistent image context in conversations
* Database changes to have `vision_enabled` option in server admin panel while configuring models
* Render previously uploaded images in the chat history, show uploaded images for pending msgs
* Pass the uploaded_image_url through to subqueries
* Allow image to render upon first message from the homepage
* Add rendering support for images to shared chat as well
* Fix some UI/functionality bugs in the share page
* Convert user attached images for chat to webp format before upload
* Use placeholder to attached image for data source, response mode actors
* Update all clients to call /api/chat as a POST instead of GET request
* Fix copying chat messages with images to clipboard

TLDR; Add vision support for openai models on Khoj via the web UI!

---------

Co-authored-by: sabaimran <narmiabas@gmail.com>
Co-authored-by: Debanjum Singh Solanky <debanjum@gmail.com>

src/khoj/processor/conversation/openai/gpt.py

@@ -123,6 +123,8 @@ def converse(
     location_data: LocationData = None,
     user_name: str = None,
     agent: Agent = None,
+    image_url: Optional[str] = None,
+    vision_available: bool = False,
 ):
     """
     Converse with user using OpenAI's ChatGPT
@@ -178,6 +180,8 @@ def converse(
         model_name=model,
         max_prompt_size=max_prompt_size,
         tokenizer_name=tokenizer_name,
+        uploaded_image_url=image_url,
+        vision_enabled=vision_available,
     )
     truncated_messages = "\n".join({f"{message.content[:70]}..." for message in messages})
     logger.debug(f"Conversation Context for GPT: {truncated_messages}")