Summary

Split jobs.json into two files: definitions (git-trackable) and runtime state (gitignored). Currently both live in a single file, making git history noisy with timestamp/status churn after every cron run.

Problem to solve

When cron.store points to a git-tracked file (e.g. ~/clawd/cron/jobs.json), every cron execution mutates runtime fields:

• state.lastRunAtMs, state.nextRunAtMs, state.lastDurationMs
• state.lastStatus, state.consecutiveErrors, state.lastDeliveryStatus
• updatedAtMs (job-level)

With ~10 daily jobs this produces 10+ meaningless commits/day, drowning real config changes in noise.

Proposed solution

Split into two files at the same directory level:

~/clawd/cron/jobs.json        # definitions only (schedule, payload, delivery, enabled, name)
~/clawd/cron/jobs-state.json  # runtime state (lastRunAtMs, nextRunAtMs, errors, etc.) — .gitignore

On load: merge state into definitions by job id.
On save: strip runtime fields from definitions file; write state separately.

The building blocks already exist in store.ts:

• stripRuntimeOnlyCronFields() already strips state and updatedAtMs
• shouldSkipCronBackupForRuntimeOnlyChanges() already compares stripped versions

A new config option could control the behavior:

"cron": {
  "store": "~/clawd/cron/jobs.json",
  "separateState": true  // default false for backward compat
}

Or infer automatically: if a .gitignore / .jj/ exists in the store directory, separate state by default.

Alternatives considered

1. jobs.d/ directory (see [Feature]: cron jobs.d/ directory support (one file per job, for NixOS/GitOps declarative setups) #20950) — solves GitOps/NixOS but not the state noise problem; complementary, not a replacement.
2. Git clean/smudge filters — fragile hack, not a real solution.
3. User-side .gitignore patterns — impossible since definitions and state live in the same file.

Impact

• Affected: any user storing cron jobs in a git/jj repo
• Severity: annoying — constant noisy diffs, meaningless commits
• Frequency: every cron run (multiple times daily)

Additional context

Related: #20950 (jobs.d/ directory support)