Restore previously logged errors for individual files but returned
success even if files failed. Now tracks failed files in RestoreResult,
reports them in the summary output, and returns an error if any files
failed to restore.
Fixes#21
The VerifySnapshotWithOptions method had a dead code path for opts.Deep
that printed 'not yet implemented' and returned nil. The CLI already
routes --deep to RunDeepVerify (which is fully implemented). Remove the
dead branch and update the VerifySnapshot convenience method to also
route deep=true to RunDeepVerify.
Fixes#2