feat(server): auto fix doc summary (#13448)

close AF-2787

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#### PR Dependency Tree


* **PR #13448** 👈

This tree was auto-generated by
[Charcoal](https://github.com/danerwilliams/charcoal)

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

## Summary by CodeRabbit

* **New Features**
* Introduced an automated system that regularly detects and repairs
documents with missing summaries in all workspaces.
* Added background processing to ensure document summaries are kept
up-to-date without manual intervention.

* **Tests**
* Added new tests to verify detection of documents with empty or
non-empty summaries.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/models/__tests__/doc.spec.ts

@@ -0,0 +1,47 @@
+import { randomUUID } from 'node:crypto';
+
+import test from 'ava';
+
+import { createModule } from '../../__tests__/create-module';
+import { Mockers } from '../../__tests__/mocks';
+import { Models } from '..';
+
+const module = await createModule({});
+
+const models = module.get(Models);
+const owner = await module.create(Mockers.User);
+
+test.after.always(async () => {
+  await module.close();
+});
+
+test('should find null summary doc ids', async t => {
+  const workspace = await module.create(Mockers.Workspace, {
+    owner,
+  });
+
+  const docId = randomUUID();
+  await module.create(Mockers.DocMeta, {
+    workspaceId: workspace.id,
+    docId,
+  });
+
+  const docIds = await models.doc.findEmptySummaryDocIds(workspace.id);
+  t.deepEqual(docIds, [docId]);
+});
+
+test('should ignore summary is not null', async t => {
+  const workspace = await module.create(Mockers.Workspace, {
+    owner,
+  });
+
+  const docId = randomUUID();
+  await module.create(Mockers.DocMeta, {
+    workspaceId: workspace.id,
+    docId,
+    summary: 'test',
+  });
+
+  const docIds = await models.doc.findEmptySummaryDocIds(workspace.id);
+  t.is(docIds.length, 0);
+});

packages/backend/server/src/models/doc.ts

@@ -696,5 +696,18 @@ export class DocModel extends BaseModel {
     return [count, rows] as const;
   }
 
+  async findEmptySummaryDocIds(workspaceId: string) {
+    const rows = await this.db.workspaceDoc.findMany({
+      where: {
+        workspaceId,
+        summary: null,
+      },
+      select: {
+        docId: true,
+      },
+    });
+    return rows.map(row => row.docId);
+  }
+
   // #endregion
 }