v0.9.0

Changed

• Gatehouse calls OpenRouter, not the Gemini API. The default model is
  openai/gpt-6-luna, with google/gemini-3.1-flash-lite as an automatic
  fallback when it is rate-limited or down. On a 33-diff replay of real
  crunchtools changes, judged blind by two models from other vendors, Luna
  caught as many reintroduced bugs as gemini-2.5-flash while nearly all of
  2.5 Flash's findings on clean PRs were noise, at about a sixth of the cost
  per review (RT #1505).
• Every request requires zero data retention and forbids training on prompts.
• --model takes an OpenRouter slug.
• A reply wrapped as {"findings": [...]} is unwrapped instead of dropped.

Added

• OPENROUTER_API_KEY_FILE: read the key from a file (wins over the
  variable; warns when the file is group- or world-readable).

Removed

• Breaking: GEMINI_API_KEY is no longer read. Replace it with
  OPENROUTER_API_KEY in ~/.config/mcp-env/gatehouse.env and in the
  GitHub secret passed to review.yml. gatehouse exits 2 with a pointer
  when only the old key is set.