feat(skills): unified /skills manager with audit and owned mutations

[SamhandsomeLee]

Summary

Delivers the Skills lane tracked on the v0.9.1 completion board (#4650): one /skills manager for inventory, audit, install/import, update, remove, and trust across CodeWhale-owned and compatible roots.

Refs #4650 (board: Skills / #4651 checkbox).
Refs #4651 (original product contract; issue was closed after load_skill listing mode — this PR completes the remaining manager / audit / mutation surface).

• Root catalog — single precedence/ownership source; only .codewhale/skills (project + global) is writable; .codex/skills is audit-only (not runtime).
• Bounded audit — unmerged inventory with Active / Shadowed / Duplicate / Conflict, package digests, provenance/trust classification, action policy; readiness stays Unknown until v0.9.1: Report artifact-skill readiness and define a managed dependency runtime #4407.
• Mutation controller — sole write path for Install / Import / Update / Remove / Trust; metadata + trust v2; TOCTOU digest checks; external roots never mutated.
• Skills Manager TUI — bare /skills opens owned-only, zero-network manager; view emits events only; host runs mutations and refreshes.
• Aliases — /skill install|update|uninstall|trust share the same controller; default install target is global owned.
• Docs/tests — docs/SKILLS.md, CONFIGURATION/GUIDE links; unit + skill_cli + Unix qa_pty coverage.

Commits

1. refactor(skills): centralize root catalog and precedence
2. feat(skills): add bounded audit inventory and status model
3. feat(skills): unify validated mutations and managed metadata
4. feat(tui): add unified skills manager view
5. test(skills): cover roots conflicts mutations and pty behavior
6. docs(skills): document manager audit provenance and readiness

Test plan

• cargo test -p codewhale-tui --bin codewhale-tui --locked skills::roots skills::audit skills::mutation skills_manager
• cargo test -p codewhale-tui --test skill_cli --locked
• cargo test -p codewhale-tui --test qa_pty --locked skills_opens_manager -- --test-threads=1 (Unix)
• Manual: bare /skills opens manager (no registry); c shows compatible; Esc closes
• Manual: import external → owned; remove/trust managed only; sentinel under .claude/skills untouched
• Manual: dual project+global same name requires --project / --global
• Confirm docs in docs/SKILLS.md match shipped behavior

Out of scope

• /skills audit CLI subcommand (manager + /skills inspect cover the need)
• v0.9.1: Report artifact-skill readiness and define a managed dependency runtime #4407 readiness probes (surface stays Unknown)
• Semantic skill comparison / second mutation stack / mutating harness roots

[github-actions]

Thanks @SamhandsomeLee for taking the time to contribute.

This repository is observing a maintainer-managed PR intake gate in dry-run mode, so this pull request is staying open. This note helps maintainers prepare the allowlist before any enforcement is considered.

Please read CONTRIBUTING.md for the expected contribution shape. A maintainer can grant recurring PR access by commenting /lgtm on a pull request.

[SamhandsomeLee]

@claude please code review

[Hmbown]

Thank you, Sam — this is in the v0.9.1 candidate with your exact 7684cbec32a355f72f0a5bd7ef996bdeddf798e0 head and all six contributor commits preserved, not squashed or rewritten. The integrated candidate is green locally across the locked TUI/workspace suites, release-contract clippy, real PTY QA, and the web gates. No action is needed from you; we will follow up here with the hosted receipt after the release branch lands.

[Hmbown]

Incorporated via #4675 (merge commit bbd0d8ba228ea74e9c9d2990c20df2d4b4cc28e9).

Ancestry receipt

• Contributor head 7684cbec32a355f72f0a5bd7ef996bdeddf798e0 is an ancestor of origin/main after Integrate CodeWhale v0.9.1 runtime and release surface #4675 merged.
• Integration head 79015d48d3cc62ecbcedbdb2d4b26731a7f71a2c is also an ancestor of origin/main.

CI receipt (on #4675 @ 79015d4)

• Test (ubuntu/macos/windows): pass
• Lint, security (cargo-audit/deny), CodeQL, DCO: pass
• Mobile smoke, workflow lint/RLM, npm wrapper: pass
• buildkite/codewhale-ci: pass (build Complete v0.7.6 TUI polish and localization lane #222)

Closing as already landed through the v0.9.1 integration gate; not merging independently so attribution and the integration graph stay intact.