Keep a concise session journal with functional chronicle and open-ended reflection. Use when a substantive session is wrapping up, when the user invokes /session-chronicle, or when the user asks to "write a journal entry", "chronicle this session", "reflect on this session", "write session notes", "summarize this session", or "what did we accomplish?". Captures decisions, failed approaches, learnings, and Claude's own reflective observations. Also handles reading past entries (/session-chronicle read) and evolving the reflective practice (/session-chronicle reflect).