No progress feedback during restore or large backup operations

[Gren-95]

Problem

When restoring a backup or creating a large one, the UI goes silent. There is no spinner, progress bar, or status update — the user has no way to tell if the operation is still running or has failed.

Acceptance Criteria

• Restore shows a progress indicator while running
• Large backup creation shows in-progress state
• If the operation fails mid-way, an error is surfaced in the UI rather than silently dropped