MM-23: Add bounded deterministic and LLM episode extraction

Parent

#771

Checkpoint

MC-7 Durable memory lifecycle

What to build

Extract explicit remember/correction deterministically and optional bounded LLM candidates with source refs, sensitivity filtering, and one retry limit.

Acceptance criteria

• Source-free candidates are rejected.
• Explicit remember and correction are recognized.
• Secrets, ephemeral progress, and derivable code facts are rejected.
• LLM extraction is capped to one call plus one retry.
• Duplicate source hashes are idempotent.

Required tests

• Explicit/correction fixtures
• sensitive/ephemeral rejection
• malformed output
• retry cap
• duplicate/restart

Benchmark

40 lifecycle extraction cases; precision >=0.95, recall >=0.85, privacy 100%.

Blocked by

• [MM-22] Add append-only EpisodeStore with exactly-once offsets #802 (MM-22)

Rollout and rollback

Disable LLM extraction and retain deterministic explicit-memory extraction only.