codebase-health/audit: Boundary routes to the sibling drift lanes

[kyle-sexton]

Parent

Refs #3803

Agent Brief

Type: Feature
Summary: The codebase-health audit skill's Boundary routes an operator to the sibling drift lanes instead of leaving them undiscoverable.

Current behavior:
The codebase-health audit skill covers doc, config, code, and architecture drift. Seven sibling skills each own a different drift dimension, and nothing in the audit skill names them. An operator who reaches this skill has no path to the others.

Desired behavior:
The audit skill's Boundary section names each sibling drift lane with one line stating what that lane owns:

• the review plugin's doc-drift detector
• the session-flow reanchor skill
• the discipline recheck-against-upstream skill
• the provenance audit skill
• the claude-config audit skill
• the instruction-placement delta skill
• the overengineering delta skill

Every reference is presence-gated: the text must read correctly whether or not the referenced plugin is installed, and must not assert that an absent skill is available. The skill's listing entry stays within the per-skill listing-entry cap; router detail belongs in the body, not in the description.

Key interfaces:

• The skill's Boundary section — gains one line per sibling lane.
• The skill's frontmatter description — unchanged in size class; must stay under the listing-entry cap.

Acceptance criteria:

• The Boundary section names all seven sibling drift lanes, each with one line on what it owns.
• Every sibling reference is presence-gated in its wording.
• /skill-quality:check passes for the codebase-health audit skill, including the listing-entry cap check.
• markdownlint passes on the changed files.
• The codebase-health plugin version is bumped per repo convention.
• The plugin README and any reference doc listing the plugin's skills reflect the change.

Out of scope:

• Changing what the audit skill detects or how it reports.
• Editing any of the seven sibling skills.
• Adding a router to any other skill.

Blocked by

None

[kyle-sexton]

Claimed by the autonomous worker lane.

• instance: vm-worker-202609050257
• lease expires: 2026-09-06T09:10:00Z (60 min TTL, renewed while active)
• scope: implement, test, independently review, open a close-linked draft PR. This lane does not merge.

Selected as one of two items in this decomposition batch that are past the 30-minute ownership window, unblocked, and clear of both live fences (lib/hook-utils.sh behind #3740, hygiene.py/destructive_guard.py behind #3783).

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Generated by Claude Code

[kyle-sexton]

[kyle-sexton]

Handoff: PR #3828 is open, close-linked and review-ready. Lease released; the merge lane owns it from here.

Seven adjacent drift lanes routed, each verified against its own frontmatter rather than recalled. The one finding worth carrying: doc-drift-detector overlaps this skill in its repo-wide no-scope mode, not in the review-diff mode, so the table splits them by question — whether a page should exist is the agent's, whether its claims are true is this skill's. Detail in #3828.

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Generated by Claude Code