fix

End-to-end bug-fix pipeline that diagnoses, implements, and proves the fix. It orchestrates /root-cause, /debugging-difficult-bugs, /test, and /check-and-commit, and performs the fix itself — the minimal code change from the proven cause plus a mandatory red→green regression test and scoped validation gates. At start it picks an autonomy mode (approval-before-each-phase vs fully autonomous) and a phase set…