hive.batch-ledger

## Operational Protocol: Batch Progress Ledger When processing a collection of items, maintain a batch ledger in `_batch_ledger`. Initialize when you identify the batch: - `_batch_total`: total item count - `_batch_ledger`: JSON with per-item status Per-item statuses: pending → in_progress → completed|failed|skipped - Set `in_progress` BEFORE processing - Set final status AFTER processing with 1-line result_summary - Include error reason for failed/skipped items - Update aggregate counts after each item - NEVER remove items from the ledger - If resuming, skip items already marked completed