feat(server): support read all notifications (#13083)

close AF-2719



#### PR Dependency Tree


* **PR #13083** 👈

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**
* Added the ability to mark all notifications as read with a single
action.
  
* **Bug Fixes**
  * Ensured notifications marked as read are no longer shown as unread.

* **Tests**
* Introduced new tests to verify the functionality of marking all
notifications as read.

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

packages/backend/server/src/core/notification/resolver.ts

@@ -100,6 +100,14 @@ export class UserNotificationResolver {
     await this.service.markAsRead(me.id, notificationId);
     return true;
   }
+
+  @Mutation(() => Boolean, {
+    description: 'mark all notifications as read',
+  })
+  async readAllNotifications(@CurrentUser() me: UserType) {
+    await this.service.markAllAsRead(me.id);
+    return true;
+  }
 }
 
 @Resolver(() => NotificationObjectType)

packages/backend/server/src/core/notification/service.ts

@@ -399,6 +399,10 @@ export class NotificationService {
     }
   }
 
+  async markAllAsRead(userId: string) {
+    await this.models.notification.markAllAsRead(userId);
+  }
+
   /**
    * Find notifications by user id, order by createdAt desc
    */