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.

frontend/src/lib/api.ts

@@ -56,6 +56,7 @@ export type ModelResource = {
   interfaceType: string;
   values: Record<string, unknown>;
   secrets: Record<string, unknown>;
+  supportImageInput: boolean;
   enabled: boolean;
   isDefault: boolean;
   updatedAt?: string | null;