omh-codebase-onboarding

[omh] Hermes Codebase Onboarding workflow: create a repo map, reading path, glossary, risk map, and first-task runway for unfamiliar codebases. Use when the user says: codebase-onboarding, codebase onboarding, repo onboarding, repository onboarding, codebase tour, code tour, new repo orientation, understand this repo.