fix(server): chunk session in migration (#13107)

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

## Summary by CodeRabbit

* **Refactor**
* Improved the process for updating session records to handle them in
smaller batches, enhancing reliability and performance during data
updates. No changes to user-facing features.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

packages/backend/server/src/data/migrations/1751966744168-correct-session-update-time.ts

@@ -1,4 +1,5 @@
 import { PrismaClient } from '@prisma/client';
+import { chunk } from 'lodash-es';
 
 type SessionTime = {
   sessionId: string;
@@ -17,16 +18,19 @@ export class CorrectSessionUpdateTime1751966744168 {
       },
     });
 
-    await Promise.all(
-      sessionTime
-        .filter((s): s is SessionTime => !!s._max.createdAt)
-        .map(s =>
-          db.aiSession.update({
-            where: { id: s.sessionId },
-            data: { updatedAt: s._max.createdAt },
-          })
-        )
-    );
+    for (const s of chunk(sessionTime, 100)) {
+      const sessions = s.filter((s): s is SessionTime => !!s._max.createdAt);
+      await db.$transaction(async tx => {
+        await Promise.all(
+          sessions.map(s =>
+            tx.aiSession.update({
+              where: { id: s.sessionId },
+              data: { updatedAt: s._max.createdAt },
+            })
+          )
+        );
+      });
+    }
   }
 
   // revert the migration