feat(server): cleanup trashed doc's embedding (#13201)

fix AI-359

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **New Features**
* Added automated cleanup of embeddings for documents deleted or trashed
from workspaces.
* Introduced a new job to schedule and perform this cleanup per
workspace daily and on demand.
  * Added new GraphQL mutation to manually trigger the cleanup process.
* Added the ability to list workspaces with flexible filtering and
selection options.

* **Improvements**
* Enhanced document status handling to more accurately reflect embedding
presence.
* Refined internal methods for managing and checking document
embeddings.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/plugins/copilot/resolver.ts

@@ -852,6 +852,14 @@ export class PromptsManagementResolver {
     return true;
   }
 
+  @Mutation(() => Boolean, {
+    description: 'Trigger cleanup of trashed doc embeddings',
+  })
+  async triggerCleanupTrashedDocEmbeddings() {
+    await this.cron.triggerCleanupTrashedDocEmbeddings();
+    return true;
+  }
+
   @Query(() => [CopilotPromptType], {
     description: 'List all copilot prompts',
   })