fix(core): filter embedding results to return only user-selected tags and documents (#11770)

Close [AI-73](https://linear.app/affine-design/issue/AI-73)

packages/frontend/core/src/components/hooks/affine/use-ai-chat-config.ts

@@ -77,6 +77,11 @@ export function useAIChatConfig() {
       const collections$ = collectionService.collections$;
       return createSignalFromObservable(collections$, []);
     },
+    getCollectionPageIds: (collectionId: string) => {
+      const collection$ = collectionService.collection$(collectionId);
+      // TODO: lack of documents that meet the collection rules
+      return collection$?.value?.allowList ?? [];
+    },
   };
 
   const searchMenuConfig = {