🎞️ feat: OpenRouter Audio/Video File Upload Support (#11070)

* Added video upload support for OpenRouter

- Added VIDEO_URL content type to support video_url message format
- Implemented OpenRouter video encoding using base64 data URLs
- Extended encodeAndFormatVideos() to handle OpenRouter provider
- Updated UI to accept video uploads for OpenRouter (mp4, webm, mpeg, mov)
- Fixed case-sensitivity in provider detection for agents
- Made isDocumentSupportedProvider() and isOpenAILikeProvider() case-insensitive

Videos are now converted to data:video/mp4;base64,... format compatible
with OpenRouter's API requirements per their documentation.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

* refactor: change multimodal and google_multimodal to more transparent variable names of image_document and image_document_video_audio

(also google_multimodal doesn't apply as much since we are adding support for video and audio uploads for open router)

* fix: revert .toLowerCase change to isOpenAILikeProvider and isDocumentSupportedProvider which broke upload to provider detection for openAI endpoints

* wip: add audio support to openrouter

* fix: filetypes now properly parsed and sent rather than destructured mimetypes for openrouter

* refactor: Omit to Exclude for ESLint

* feat: update DragDropModal for new openrouter support

* fix: special case openrouter for lower case provider

(currently getting issues with the provider coming in as 'OpenRouter' and our enum being 'openrouter') This will probably require a larger refactor later to handle case insensitivity for all providers, but that will have to be thoroughly tested in its own isolated PR

---------

Co-authored-by: Claude Sonnet 4.5 <noreply@anthropic.com>
Co-authored-by: Dustin Healy <54083382+dustinhealy@users.noreply.github.com>

client/src/components/Chat/Input/Files/__tests__/AttachFileMenu.spec.tsx

@@ -512,7 +512,7 @@ describe('AttachFileMenu', () => {
   });
 
   describe('Google Provider Special Case', () => {
-    it('should use google_multimodal file type for Google provider', () => {
+    it('should use image_document_video_audio file type for Google provider', () => {
       mockUseAgentToolPermissions.mockReturnValue({
         fileSearchAllowedByAgent: false,
         codeAllowedByAgent: false,
@@ -536,7 +536,7 @@ describe('AttachFileMenu', () => {
       // The file input should have been clicked (indirectly tested through the implementation)
     });
 
-    it('should use multimodal file type for non-Google providers', () => {
+    it('should use image_document file type for non-Google providers', () => {
       mockUseAgentToolPermissions.mockReturnValue({
         fileSearchAllowedByAgent: false,
         codeAllowedByAgent: false,
@@ -555,7 +555,7 @@ describe('AttachFileMenu', () => {
       expect(uploadProviderButton).toBeInTheDocument();
       fireEvent.click(uploadProviderButton);
 
-      // Implementation detail - multimodal type is used
+      // Implementation detail - image_document type is used
     });
   });