Add support for image input in model resources and enhance related configurations

- Introduce a new `support_image_input` field in model resources, allowing models to indicate support for image input.
- Update the backend models, schemas, and database seed scripts to accommodate the new field.
- Enhance the AssistantConfig and related routes to handle image input capabilities, ensuring proper validation and error handling.
- Modify the frontend components to include toggles for enabling visual understanding and filtering models based on image input support.
- Implement necessary adjustments in the voice preview and pipeline to integrate video stream handling alongside audio functionalities.

backend/schemas.py

@@ -111,6 +111,7 @@ class ModelResourceUpsert(CamelModel):
     interface_type: str
     values: dict[str, Any] = Field(default_factory=dict)
     secrets: dict[str, Any] = Field(default_factory=dict)
+    support_image_input: bool = False
     enabled: bool = True
     is_default: bool = False