$ node scripts/demo-crash-recovery.mjs
▶ 1. Stage a 2-file change (PostgreSQL: krusch_staged_diffs)
   disk  src/moduleA.js  // moduleA: ORIGINAL
   disk  src/moduleB.js  // moduleB: ORIGINAL
   disk  temp files      (none)
   db    src/moduleA.js    status=PENDING
   db    src/moduleB.js    status=PENDING

▶ 2. applyDiffBatch() in a child process; SIGKILL right after file 1 is renamed
   child exited with signal SIGKILL

▶ 3. Torn state left behind by the crash
   disk  src/moduleA.js  // moduleA: UPDATED
   disk  src/moduleB.js  // moduleB: ORIGINAL
   disk  temp files      .moduleB.js.krusch-tmp-1793942668205-194c1e24
   db    src/moduleA.js    status=APPLYING
   db    src/moduleB.js    status=APPLYING

▶ 4. Restart → recoverInFlightApplies()
   recovery  diff 5240 → BATCH_ROLLBACK_REVERTED_TO_PENDING
   recovery  diff 5241 → BATCH_ROLLBACK_REVERTED_TO_PENDING

▶ 5. State after recovery
   disk  src/moduleA.js  // moduleA: ORIGINAL
   disk  src/moduleB.js  // moduleB: ORIGINAL
   disk  temp files      (none)
   db    src/moduleA.js    status=PENDING
   db    src/moduleB.js    status=PENDING

✅ Both files are back to their original content, the temp file is gone,
   and both rows are PENDING again, ready for a clean re-apply.