Add backupList GraphQL API for Listing Available Backups with Pagination Support

[msk]

Summary:

We need to add a new GraphQL API, backupList. This API should return a list of currently available backups with full BackupInfo details, as returned by review_database::backup::list. Importantly, the API should support pagination using after, before, first, and last arguments.

Proposed Changes:

1. Implement a new GraphQL API backupList in the review-web project.
2. The backupList API should return a list of BackupInfo details as returned by review_database::backup::list.
3. Include support for pagination within backupList, accepting after, before, first, and last arguments.

Acceptance Criteria:

1. A new GraphQL API backupList is implemented and tested.
2. The backupList API correctly returns a list of all BackupInfo details as returned by review_database::backup::list.
3. The backupList API successfully implements pagination and accurately returns data according to after, before, first, and last arguments.