Setup harness

Adapted from mattpocock/setup-matt-pocock-skills. Run once per consuming repo.

Ask the user

1. Issue tracker: GitHub (gh) · GitLab (glab) · local .scratch/ · other (one paragraph)
2. Triage labels: Confirm or customize docs/agents/triage-labels.md
3. Domain docs path: Default docs/domain/ — ok?
4. RAG: Enable Neon embeddings? → point to docs/rag/neon-doppler-setup.md
5. Instruction file: AGENTS.md (canonical). If CLAUDE.md exists, add one line: @AGENTS.md

Write / update