document-feature

Create user-facing feature documentation for the docs VitePress docs site. Analyzes the codebase and produces an index.en.md in the correct docs directory. Use when user says 'document this feature', 'write feature docs', 'create docs for X', 'add feature to docs site', or 'user-facing documentation for'. Takes feature name as argument. Do NOT use for ADRs (use /document-decision) or syncing existing docs (use…