Use Iceberg catalog for backup, restore, and time travel

[Skeletrox]

Replace the existing backup/restore functionality with the new Iceberg catalog implementation.

Key requirements:

1. Automatically take a backup (checkpoint) as part of every completed write transaction (Update, create or delete).
2. Allow users to list available versions/snapshots.
3. Enable 'time travel' to a specific version (defaulting to latest).
4. On a time-traveled snapshot, only read operations should be permitted.
5. Integrate with the existing socket interface (Backup/Restore requests).