- Track progress in a per-batch JSON state file after each article so
a mid-run crash leaves a recoverable checkpoint
- Add `maxRetries` parameter to generateBatch() with per-article retry
loop (default: 1 extra attempt)
- Add `resumeBatch()` to re-process only failed/pending articles,
skipping those already successfully generated in a prior run
- Add `loadBatchProgress()` public method for inspecting state
- State stores per-article status, attempt counts, error messages,
and timestamps for full observability
Tests: 6 new scenarios covering state persistence, resume capability,
retry logic, and the no-state error case
Closes#27
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
