✨ feat: Add subfolder support for model specs (#9165)

- Add optional `folder` field to TModelSpec type and schema
- Create ModelSpecFolder component for hierarchical display
- Implement expand/collapse functionality for folders
- Update search results to show folder context
- Sort folders alphabetically and specs by order/label
- Maintain backward compatibility (specs without folders appear at root)

This enhancement allows organizing model specs into categories/folders
for better organization and improved user experience when dealing with
many model configurations.

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

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

packages/data-provider/src/models.ts

@@ -19,6 +19,7 @@ export type TModelSpec = {
   showIconInHeader?: boolean;
   iconURL?: string | EModelEndpoint; // Allow using project-included icons
   authType?: AuthType;
+  folder?: string; // Optional folder/category for grouping model specs
 };
 
 export const tModelSpecSchema = z.object({
@@ -32,6 +33,7 @@ export const tModelSpecSchema = z.object({
   showIconInHeader: z.boolean().optional(),
   iconURL: z.union([z.string(), eModelEndpointSchema]).optional(),
   authType: authTypeSchema.optional(),
+  folder: z.string().optional(),
 });
 
 export const specsConfigSchema = z.object({