Harden LLM cache files, diff snapshots, and approval ID indexes against truncated or malformed JSON after process termination.
Disposable cache and snapshot corruption now recovers as a miss; authoritative resume state still surfaces malformed JSON. Approval short-ID indexes use atomic no-overwrite publication and degrade to full resume-token approval when the index cannot be published durably.
Closes#111.
Closes#112.
Closes#113.
Co-authored-by: Andy Ye <35905412+TurboTheTurtle@users.noreply.github.com>
