chameleon 2.15.0

Refresh now derives from the genuinely-latest production, not the user's last
fetch. When a repo has a locked production_ref, /chameleon-refresh and the
background auto-refresh run one bounded git fetch origin <branch> before
resolving the tip — DEFAULT-ON, the one network path made default-on by design.

Added

• Production-ref fetch-before-refresh (auto_refresh.fetch_production_ref,
  default true; kill switch CHAMELEON_FETCH_PRODUCTION_REF=0). Before refresh
  resolves the locked production tip, it fetches origin <branch> so the
  derivation sees the latest production rather than whatever the user last
  fetched. One fetch site in refresh_repo serves both manual and auto-refresh;
  bootstrap/init never fetch. The outcome rides out in the refresh envelope's
  production_ref_fetch block and auto_refresh.log, so a stale derivation
  always says WHY.
  • Hang-proof + non-interactive. The fetch runs with GIT_TERMINAL_PROMPT=0,
    an empty askpass, and SSH BatchMode=yes so a missing credential is a clean
    failure, never a prompt; a hard CHAMELEON_PRODUCTION_REF_FETCH_TIMEOUT_SECONDS
    (default 10) wall-clock plus a process-group SIGKILL (taskkill tree on
    Windows) backstops a stuck transfer.
  • Fails open, classified, surfaced. Any non-ok outcome (timeout /
    no_network / auth / no_remote_ref / concurrent / unknown) falls back to the
    existing last-fetched ref and reports a specific reason — the auth reason
    tells the user the exact git fetch origin <branch> to run by hand.
  • Self-suppresses where a surprise network call is wrong. Off under CI,
    off when the branch is not origin-backed (re-detected, not inferred), and a
    CHAMELEON_PRODUCTION_REF_FETCH_BACKOFF_HOURS (default 6) backoff after a
    persistent auth/branch-gone failure so a misconfigured remote isn't re-hit
    every session. NO fetch on any hook hot path (PreToolUse/PostToolUse/
    SessionStart stay offline).

This is a deliberate, single exception to the "network paths stay opt-in"
principle, made default-on by maintainer decision and surfaced here rather than
buried. Designed via a multi-agent panel with adversarial review; shipped with a
fake-git-shim test battery (classifier, timeout-kill, non-interactive env,
backoff) plus real-local-origin integration and hot-path no-fetch assertions.