FileApplicationJournal

Authoritative local-filesystem journal. Every successful write includes the file/directory durability barriers; SwayDB or other indexes may be rebuilt from this history. Unsupported atomic moves or directory force fail closed. Deployment requires a trusted local filesystem that honors those JDK durability operations; this backend cannot attest remote filesystem behavior.

Opening acquires an exclusive process lock but leaves the backend fenced. Call recover before any write or ordinary blob read. A truncated frame is retained unchanged and never treated as evidence that a claim was absent.