- Remove PurgeSnapshots wrapper; callers use PurgeSnapshotsWithOptions directly
- Update snapshot create --prune to call PurgeSnapshotsWithOptions
- Remove TestSnapshotPurgeOptions (tested Go struct assignment, no value)
- Remove legacy no-name snapshot tests (TestPurgeKeepLatest_LegacyNoNameSnapshots,
TestPurgeKeepLatest_MixedNamedAndLegacy)
- Remove legacy format test cases from TestParseSnapshotName
- Update parseSnapshotName doc to not mention legacy format
