chore(server): add auto index batch size (#12391)

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

- **New Features**
  - Added a configurable batch size setting for automatic workspace indexing. Users can now adjust how many workspaces are indexed per batch, with a default value of 10 and support for values between 1 and 1000.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/plugins/indexer/config.ts

@@ -19,6 +19,9 @@ declare global {
         username: string;
         password: string;
       };
+      autoIndex: {
+        batchSize: number;
+      };
     };
   }
 }
@@ -58,4 +61,9 @@ defineModuleConfig('indexer', {
     default: '',
     env: ['AFFINE_INDEXER_SEARCH_PASSWORD', 'string'],
   },
+  'autoIndex.batchSize': {
+    desc: 'Number of workspaces automatically indexed per batch',
+    default: 10,
+    shape: z.number().int().positive().max(1000),
+  },
 });

packages/backend/server/src/plugins/indexer/job.ts

@@ -121,7 +121,7 @@ export class IndexerJob {
         indexed: true,
       });
     }
-    this.logger.debug(
+    this.logger.log(
       `indexed workspace ${workspaceId} with ${missingDocIds.length} missing docs and ${deletedDocIds.length} deleted docs`
     );
   }
@@ -138,7 +138,10 @@ export class IndexerJob {
   @OnJob('indexer.autoIndexWorkspaces')
   async autoIndexWorkspaces(payload: Jobs['indexer.autoIndexWorkspaces']) {
     const startSid = payload.lastIndexedWorkspaceSid ?? 0;
-    const workspaces = await this.models.workspace.listAfterSid(startSid, 100);
+    const workspaces = await this.models.workspace.listAfterSid(
+      startSid,
+      this.config.indexer.autoIndex.batchSize
+    );
     if (workspaces.length === 0) {
       // Keep the current sid value when repeating
       return JOB_SIGNAL.Repeat;