ax:retro - guided experiment-loop session

Closes the self-improvement loop. Claude orchestrates ax improve … commands; the user decides each row.

Assumes ax (axctl) is on PATH. If ax improve list fails, tell the user to check docs/development.md#setup (DuckDB dylib setup - no daemon required) and stop.

When to fire

ONLY fire on explicit triggers:

• "let's do an ax retro" / "ax retrospective" / "retro time"
• "review my ax proposals" / "triage proposals"
• "what's my experiment loop status" / "lock pending verdicts"
• "hook effectiveness review" / "intervention review"
• "self-improvement session"
• /ax:retro slash command (if the plugin marketplace publishes one)