V4.04: Add retry_transient() to dlq_manager — re-enables reported transient
failures for retry with --retry CLI flag, increments retry_count/last_retry
V4.05: save_report() now truncates JSONL to MAX_REPORT_HISTORY entries
after each append (best-effort rotation)
V4.06: Wrap datetime.fromisoformat() in try/except (ValueError, TypeError)
in get_status_summary() — skips entries with malformed timestamps
V4.08: Replace body[:50] dedup key with hashlib.sha256(body).hexdigest()
in fabric-retrieve.py deduplicate()
V4.09: Add OrderedDict LRU cache (256 entries) to embedding.py get_embedding()
— avoids recomputing embeddings for repeated text