feat(hooks): robust git-hook registration + lefthook support (2.3.0)

[jurby]

Problem

Git hooks could silently stop firing — most visibly the post-commit local_evidence.py emitter, so contribution evidence stopped landing on items (the reported bug). Two root causes:

1. install_hooks used a blunt not dst.exists() guard — if a slot was already occupied (typically by lefthook, which owns .git/hooks/), EDPA silently skipped its hook.
2. After a plugin update, update_engine.sh re-vendored the engine but never re-registered hooks; the copies in .git/hooks/ went stale / missing.

Fix

• Robust install_hooks — hooks carry an EDPA-MANAGED-HOOK sentinel; per slot: install when missing, refresh when EDPA-owned, never clobber a foreign hook (warns + prints the exact chain-in line).
• lefthook support — detects lefthook.yml and prints a paste-ready snippet (with use_stdin: true on pre-push, or lefthook hangs) instead of touching .git/hooks/. EDPA never edits the user's lefthook config.
• Self-heal — update_engine.sh re-registers EDPA hooks after a version bump when the project already uses them (opt-out repos untouched).
• New --check-hooks (read-only doctor) and --refresh-hooks (register-only) flags.
• scripts/hooks/install.sh → thin delegator (drops the conflicting core.hooksPath); removed dead generic pre-commit; ANSI now TTY-aware.

Docs / web

RUNBOOK §1+§6, quick-start, skills/setup/SKILL.md, playbook.md, README ×2, E2E-TEST-PLAN, plus website setup/guide/playbook/methodology (CZ + EN). Documents the lefthook snippet, foreign-hook behavior, and --check-hooks verification.

Tests

New tests/test_project_setup_hooks.py (fresh install, refresh, foreign-skip, lefthook snippet validity) + self-heal cases in tests/test_update_engine_hook.py. Full suite: 618 passed.

Release

Version bumped to 2.3.0 (plugin.json + web/package.json + CHANGELOG). Web deploy + gh release to follow after merge.

🤖 Generated with Claude Code

[jurby]

Superseded by #57 — same work, branch renamed to defect/D-1-hook-registration so it satisfies the EDPA branch-naming convention (dogfooding the very convention this PR strengthens).