v0.7.1: fix delete version-guard bypass on tombstones A stale ?version against an already-deleted object answered 200 instead of 409, so the edit-vs-delete race guard never ran on tombstones. Delete() now evaluates the version guard before the idempotent re-delete no-op. The compare-tool fixture is updated to expect the corrected behavior. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>