Result of a per-key maintenance entry point (HyperDir::recover_intent /
HyperDir::process_reclaim): lets an event-driven caller decide whether to
ack the triggering event or retry it. Transient/busy conditions surface as
Err(ResourceBusy) (retry), not as a variant.
Wall-clock age beyond which a _TXN/ intent (rename .intent, reclaim
.reclaim, or link .link) is treated as abandoned rather than the
in-flight tail of a live op. Exposed so an external maintainer can pick stale
intents off an S3 Inventory listing by the object’s ULID/mtime.