refactor(kyberforge)!: merge skill-audit and agent-audit into factory-audit

Why

The two audit skills carried 1,724 lines of byte-identical duplication: the ADR-0020 boundary
resolver (1,061), vale-wrap.sh (526), the Vale style rules (44) and the Contributing-files parser
(93). Nothing shared them — they were held in sync by a 413-line pre-push gate and its 797-line
test suite. Sync-by-gate had already failed once: at 484357a the two parser copies drifted into
different spellings of the bullet loop while a docstring asserted they were identical. That drift
was behaviour-neutral and was re-unified by hand at 598a7c3, so the copies were identical at merge
time — but nothing had caught it, and the next drift need not be neutral.

Implementation Notes

Self-containment binds BETWEEN skills, not within one. The agentskills.io spec forbids reaching
across skill directories, which is why two separate skills needed embedded copies; two files inside
ONE skill may source a third. That is the whole reason the merge removes duplication rather than
relocating it.

The union of both bodies measured 1,532 words against BODY_MAX_WORDS=900, and only 211 of those
words were shared, so SKILL.md is a dispatch body. Step 0 resolves the flow from the target path
before any validation, and its table mirrors validate.sh's detection exactly: a directory holding
SKILL.md or a SKILL.md file (skill); a *.agent.md, or a .md directly under an agents/ directory
(agent); anything else stops without running a validator. Steps 1-3 live in
references/skill-flow.md and references/agent-flow.md, and gotchas that apply to one flow live in
that flow's file, since it is loaded on every invocation anyway. If validate.sh reports on the
other artifact type, the body restarts at Step 0.

Named factory-audit rather than forge-audit because forge is a live skill, and a family prefix that
matches a live sibling reads as ownership rather than membership.

The description carries one arrow per boundary target, because ADR-0020 resolves only the first
target after an arrow. It drops the quoted "audit this skill"-style phrases, which restated
"audited" in a second register (ADR-0020's duplicate-register rule). 241 characters, Gotchas 16%
of the body: no size SUGGESTIONs.

The boundary resolver stays embedded in two files rather than imported: a cache-installed plugin
cannot read outside its own directory, and the repo-root hook resolves via .pre-commit-hooks.yaml
where entry[0] is the only token pre-commit rewrites, so no single file is reachable by both.
tests/test-adr0020-contract.sh hashes both copies for byte-identity, and asserts validate.sh sources
the resolver and that no third copy exists.

The entry scripts classify the target from its resolved parent directory, so a bare agent filename
typed inside agents/ works; resolve SCRIPT_DIR CDPATH-safely; and exit 2 when a lib-*.sh is
missing, rather than dying with exit 1, the tier the flows relay as real findings.

The provenance run functions stash their findings code in KYBERFORGE_PROV_RC and
return 0, so validate-provenance.sh calls them UNTESTED. Testing a function's
status (`f || RC=$?`) disables errexit for its entire body, and no subshell or
`set -e` inside can re-arm it once the call sits in a condition context
(measured, both spellings). Their error paths use `exit`, which is unaffected
either way; this keeps errexit armed for anything added later.

Case 0's readability guard reads the file instead of asking `[[ -r ]]`. `-r` is
access(2), which answers yes for uid 0 even on a mode-000 file, and this repo's
dev environment is root -- so the guard could never fire where it exists to fire.
A read attempt is also the stricter question, catching EIO. This is the reasoning
scripts/check-vale-style-sync.sh carried before this commit deleted it; the
hazard did not go with it.

All three entry scripts are CDPATH-safe, vale-wrap.sh included: both of its cd sites are cleared,
the --config resolution and the directory-mirror walk, where an exported CDPATH would otherwise
print a decoy path into the -print0 stream and build the mirror from the decoy's files. The two
remaining bare cd calls take absolute paths, which CDPATH is never consulted for.

Impact

BREAKING: skill-audit and agent-audit no longer exist as invocable skills. kyberforge goes to
2.0.0 (catalog 0.4.7).

Check logic is unchanged: differential runs of the old and new validators across every skill and
agent produced byte-identical stdout, stderr and exit codes, and the reconstructed Python payloads
differ only in comments and the references/field-inventory.md -> agent-field-inventory.md rename.
One doctrine governs the tiers: exit 0 is audited and clean, exit 1 is audited with findings OR a
target present but unreadable, exit 2 is that nothing was audited at all. Edge paths DID change,
deliberately (full table in ADR-0025):
- a missing target exits 2 (never ran), not 1, under its own "does not exist" message; detection is
  by path shape, so a shape-matching path that is simply absent used to reach the validator and come
  back as a FAIL against a file that never existed;
- an unshaped target exits 2 under the generic "matches neither" message, and a directory with no
  SKILL.md under a third, distinct one -- three exit-2 messages, not one;
- a dangling symlink or a symlink loop stays exit 1: it is present but broken, which is a finding
  about the artifact rather than a usage error;
- a SKILL.md file path is audited as its skill directory instead of refused;
- a .md agent outside an agents/ directory is refused rather than audited;
- a missing script library, a missing python3, a missing PyYAML, and no argument at all each exit 2.
  validate-provenance.sh already exited 2 for the last two; validate.sh now matches it.

.pre-commit-hooks.yaml is a published contract consumed by external repos. Both hook IDs and both
files: regexes are unchanged; only entry: and description: moved.

scripts/check-vale-style-sync.sh (413), scripts/sync-vale-styles.sh (21),
tests/test-check-vale-style-sync.sh (797) and agent-audit/scripts/README.md (47) are deleted. The
checker made 17 assertions: 6 compared the two Vale copies and are moot; 10 are rehomed into
tests/test-vale-wrap.sh (case 0, cases 28-31, and the suite's Vale-absent skip); and the
cross-manifest files: agreement check, which selected hooks by entry: and so could not survive both
hooks sharing one, is ported as case 33 pairing hooks by id:. Cases 28, 30 and 33 carry mutation
self-tests; narrowing the local skill prefilter to 6 of 38 SKILL.md files now fails the suite.

Skills go 39 to 38. Pre-push goes 9 repo-authored hooks to 8.

ADR: 0025
BREAKING-CHANGE: the skill-audit and agent-audit skills are removed. Both flows are served by
  factory-audit, which auto-detects whether it was handed a skill directory or an agent file.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YR2CjVumUbEGWcMikcoXBD

plugins/kyberforge/.apm/skills/factory-audit/references/agent-description-quality.md

@@ -0,0 +1,96 @@
+---
+source_keys:
+  - context7-websites-code-claude
+  - claude-code-subagents-docs
+  - context7-github-en-copilot
+  - github-custom-agents-configuration
+---
+
+# Agent Description Quality Reference
+
+Upstream source: Claude Code subagent reference, GitHub Copilot custom-agents configuration.
+House contract: the context budget. The house contract is narrower than either
+platform's schema rather than a reinterpretation of it: where both speak, both must be satisfied.
+
+## Why the description is the expensive part
+
+At startup an agent loads only the `name` and `description` of every installed skill and agent.
+The body is never seen until the agent is invoked. The description therefore carries the entire
+triggering burden **and** is paid for in every session, whether the agent fires or not.
+
+A second cost is less obvious and is a correctness hazard rather than a token cost: a description
+that summarises the workflow is a shortcut the caller takes *instead of* reading the body. A
+measured failure upstream — a description saying "code review between tasks" — produced one review
+where the body's flowchart specified two.
+
+## Step 0 — establish which contract applies
+
+Read the frontmatter before judging a single word.
+
+- **`disable-model-invocation: true`** — the agent is hand-invoked. Its description is never
+  matched against user intent, so it is not a routing string. It carries **one plain human-facing
+  sentence** stating what the agent does. Audit it for that and nothing else. Reporting a missing
+  trigger clause, a missing boundary clause or absent indirect triggers on a hand-invoked agent is a
+  wrong finding, not a strict one. The field is Copilot-only and not on the vendor-neutral APM
+  allowlist, so this case arises in a Copilot `.agent.md` at project/user scope and nowhere else.
+  Its Claude Code counterpart has no equivalent field and stays model-invoked, so the two halves of
+  the pair carrying differently shaped descriptions is expected there rather than a
+  pair-consistency finding.
+  `user-invocable: false` does not belong in this bullet. The two are separate fields with opposite
+  defaults — `disable-model-invocation` (default `false`) governs runtime auto-selection,
+  `user-invocable` (default `true`) governs manual invocation, and the retired `infer` field was
+  replaced by the pair rather than by either one. So `user-invocable: false` says nothing about
+  whether the agent is model-routed: judge that from `disable-model-invocation` alone, and where
+  that is absent the three-part shape below still applies. `user-invocable` carries no
+  description-quality contract of its own and is out of this file's scope entirely.
+- **No such flag** — the agent is model-invoked and the rest of this file applies.
+
+## The three-part shape
+
+A model-invoked description carries exactly three things:
+
+1. **Trigger clause.** When to invoke, phrased imperatively: `Use when ...`. Not `This agent ...` —
+   the caller is deciding whether to act, not reading a catalogue entry.
+2. **At most one capability clause.** What it does, in one clause. Never an enumeration.
+3. **Boundary clause.** Compressed form: `Not <thing> -> <skill-name>.` The target must resolve to
+   a real skill directory or agent file in the authoring source.
+
+Everything else belongs in the body or in the plugin's `README.md`.
+
+## Indirect triggers — conditional, never blanket
+
+Add "even if the user doesn't say X" **only where the user's natural phrasing genuinely omits the
+domain word.** True for the `gitea-*` family: people say "create an issue", not "create a Gitea
+issue". False for `git-commits`: nobody asks for a commit without saying commit. A blanket
+indirect-trigger clause on an agent whose domain word is unavoidable is padding charged to every
+session.
+
+## Near-miss exclusions
+
+Add a boundary clause only where a sibling skill or agent could plausibly steal the activation. Use
+strong near-misses — queries that share keywords but need something different — not weak ones. One
+boundary clause per genuine near-miss; a list of four is enumeration wearing a boundary's clothes.
+
+## Before / after
+
+```yaml
+# FAIL — a noun-phrase opener rather than a trigger, capability enumeration in
+# place of one capability clause, and no boundary clause at all, preloaded into
+# every session forever. (The live git-orchestrate description, 254 chars.)
+description: Orchestrates git workflow operations for other agents. Invoke when a
+  caller needs a multi-step or destructive git operation (rebase, force-push, branch
+  deletion) coordinated across domain skills with safety gates, session context, and
+  structured results.
+
+# PASS — trigger, one capability clause, boundary. The operation list and the
+# safety-gate mechanics are the body's job; the router cannot act on them.
+description: >
+  Use when an agent caller needs a multi-step or destructive git operation
+  dispatched and safety-gated. Not conversational git help -> git-workflow.
+```
+
+## Where the criteria live
+
+Every FAIL and SUGGESTION criterion for this dimension is in `references/agent-finding-criteria.md`,
+which Step 3 reads on every run. This file is the reasoning behind them, loaded only when that file
+puts the description dimension in play.