ArtifactFS 1.0.0-rc.8

This release improves observability and retry logic, adding NDJSON log output to the daemon operations on repo add/remove/fetch events, as well as upstream retry and backoff handling.

• Emit structured preparation lifecycle records with repository, mode, source, attempt, phase, state, duration, deadline, and snapshot details; no new logging configuration is required.
• Retry transient clone and fetch failures up to three total attempts, using jittered backoff capped at 250 ms and then 1 second; authentication, permission, quota, and disk failures still fail immediately.
• Reuse existing Git directories safely during re-registration by updating the remote, fetching the selected ref, advancing the branch, and rebuilding the snapshot as separate observable phases.
• Cap Git diagnostics at 16 KiB, redact credentials and complete remote references, and stop Git commands and pending backoff when preparation is canceled.
• Persist preparation state with version checks and per-repository locks so stale attempts cannot overwrite newer registrations, while preserving staged index entries and leaving HEAD unchanged on conflicts.