Add API autodoc pages (Config, Enterprise, Sanitizer), introductory
prose on all 10 API pages, troubleshooting guide, enterprise guide,
scoring cadence reference, validation rules reference. Update ROADMAP
to reflect v2.2.0 as current. Bump version to 2.2.1.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>