fix(claude): support skills-dir plugin installs

[malinskibeniamin]

Summary

• Replace Claude Code marketplace install with the v2.1.157+ skills-directory clone flow.
• Teach verify-install to recognize ~/.claude/skills/frontend-skills plugin installs and avoid stale cache namespaces.
• Bump Claude/Codex manifests, marketplace manifests, skill manifest, changelog, and pinned README release to 4.11.1 / 2026-06-10.
• Add a README smoke check that proves Claude itself sees the skills-dir plugin.
• Fix related harness validation/eval issues found while opening the PR: metrics summary now runs on SessionEnd, adversarial reviewer frontmatter validates, branch-safety eval works in detached worktrees, and scope-lock stays silent for pure questions.

Commits

• fab92fb fix(claude): support skills-dir plugin installs
• e579a36 fix(hooks): run metrics summary on session end
• 2deb454 fix(agents): quote adversarial reviewer metadata
• daf0f26 test(worktree): stabilize branch safety eval
• ca040db fix(hooks): keep scope-lock silent for questions
• 80dfdc3 fix(install): drop stale cache namespace fallback
• 833eb1d test(install): document cli plugin smoke check
• 319ef59 chore(release): bump plugin metadata to 4.11.1

Screenshots / surface review

View	Before	After	Notes
README install flow	Marketplace commands (/plugin marketplace add, /plugin install)	git clone into ~/.claude/skills/frontend-skills + claude plugin list smoke check	Text-only setup flow; legacy marketplace path kept behind details fallback.

Test plan

• ./evals/run.sh --json -> 2200 passed, 0 failed, 0 skipped
• ./evals/run.sh version-metadata --json -> 15 passed, 0 failed, 0 skipped
• ./evals/run.sh manifest-codegen --json -> 7 passed, 0 failed, 0 skipped
• ./evals/run.sh plugin-marketplace --json -> 8 passed, 0 failed, 0 skipped
• ./evals/run.sh claude-skills-dir-install --json -> 7 passed, 0 failed, 0 skipped
• claude plugin validate .claude-plugin/plugin.json -> passed with warnings only
• Clean HOME remote smoke: clone PR branch into $HOME/.claude/skills/frontend-skills; claude plugin list | grep 'frontend-skills.*skills-dir' -> loaded, version 4.11.1
• Clean HOME remote smoke: bash ~/.claude/skills/frontend-skills/scripts/verify-install.sh --json -> {"pass":35,"warn":2,"fail":0,"version":"4.11.1","updatedAt":"2026-06-10"}

🤖 Generated with Claude Code