Module checkpoint 

Shared checkpoint kind policy for cloud substrates.

Known ephemeral kinds (action, source-ref when it owns no checkout) are Gone / Ok on observe/destroy. Unknown kinds fail closed so a typo or old binary cannot drop a journal row while leaving a live resource.

Functions

is_ephemeral_resource_kind

Resource kinds that own nothing destructible on every cloud substrate.

parse_payload

Parse a checkpoint payload: empty → Ok(None) (legacy fallback); non-empty malformed → Err(detail); valid → Ok(Some(T)).