feat(cron): add durable execution audit history

[teknium1]

Summary

Cron execution attempts now have bounded, indexed, restart-safe audit history with truthful unknown outcomes and an operator inspection surface.

Changes

• Persist claimed → running → completed/failed/unknown attempts in profile-local cron/executions.db before executor/provider dispatch.
• Make terminal transitions immutable and classify abandoned attempts only after PID + process-start fingerprint proves the owner is gone.
• Bound terminal retention while never pruning active attempts; use indexed pagination and batch latest-attempt lookup.
• Fail closed on corrupt ledger state instead of silently replacing audit history.
• Finish rejected executor submissions and release the in-process running guard on every exception path.
• Centralize recovery in the scheduler-provider ABC so built-in, Chronos, and standalone providers share the same contract.
• Add hermes cron runs [job-id] --limit N / history, quick-backup coverage, and English/Chinese docs.

Validation

Check	Result
Targeted cron/CLI/backup suites	566 passed
Real two-process restart E2E	Running attempt restored as unknown; no retry manufactured; CLI showed original ID
Windows footgun audit	758 files clean
git diff --check	Passed

This PR is intentionally held unmerged for soak and review after CI.

Infographic