feat: repo health & onboarding-readiness report (HEALTH.md)

[Arthur742Ramos]

Summary

Adds a deterministic (AI-free) repo-health & onboarding-readiness report — a new flagship HEALTH.md document that scores how easy a repository is for a new contributor to get productive in.

It answers the onboarding question the README poses ("Most READMEs are outdated… most wikis incomplete") with hard signals: does the project have docs, community files, quality tooling, and automation?

What it checks

Computed entirely from the file scan (stable across runs), grouped into four categories with weighted scoring:

• Documentation — README (+ depth), LICENSE, CONTRIBUTING, CHANGELOG
• Community — Code of Conduct, Security policy, Issue/PR templates, CODEOWNERS
• Quality — automated tests, linter config, formatter config, EditorConfig, .gitignore
• Automation — CI, dependency automation (Dependabot/Renovate), git hooks / pre-commit

Output: a weighted 0–100 score + A–F grade, per-category status tables, and a prioritized list of recommendations (highest-impact gaps first).

Meta-file detection is anchored to the repo root and conventional meta dirs (.github/, docs/), so a source file like src/security.ts is never mistaken for a SECURITY policy.

Changes

• src/health.ts — computeRepoHealth(), generateHealthDocs(), getHealthGrade()
• Wired into the generation pipeline (analysis-orchestration.ts), gated by a new showHealth style-pack section (enabled for all packs except minimal)
• bootcamp run summary now prints a Repo Health line; HEALTH.md listed in generated files
• Public API: ./health package subpath export + re-exports from src/api.ts
• Docs: README (features, file table, demo tree) + CHANGELOG

Testing

• test/health.test.ts — 13 unit tests (scoring, grade thresholds, warn=half-weight, path anchoring, CI/test-naming detection, Windows path normalization, doc rendering, empty-scan safety)
• Extended test/e2e/cli-main.e2e.test.ts to assert HEALTH.md is produced by the real CLI process
• Local validation: lint ✓, typecheck ✓, build ✓, full unit suite 1032 passing, CLI e2e ✓