* feat: add opt-in task notes and compacted history recall
* fix: validate task continuity state and preserve user answers
Honor explicit opt-out, preserve clarification replies and capture failure statuses, validate notebook writes, and clear branch archive references. Update the config version and audit optional LLM credentials, with regression and integration evidence.
* fix: align Helm config version with task continuity schema
* fix: preserve mixed task history and declare continuity policies
* fix: recover malformed history and evict archives atomically