fix(kyberforge): reconcile the authoring rules the ADR-0020 trim left disagreeing

Six defects, each one a place where two files that an author reads in the same
sitting told them different things — or where the trim dropped a rule and nothing
noticed because no gate covers prose.

**"Use proactively" contradicted itself across the pair.** All three agent
templates said to add it where the runtime should delegate unprompted, while
`agent-audit`'s `KyberforgeCopilot.ProactivePhrase` rule grades it a hard FAIL in
any `*.agent.md` — which is the Copilot half of every project/user pair *and* the
vendor-neutral plugin-scope file, since that compiles to a real Copilot agent
downstream. Following the template produced a file the repo's own gate rejects.
The phrase is now permitted in exactly one place, the Claude Code `.md`, and
`references/contract.md` carries the per-file table plus the consequence authors
ask about next: a pair whose CC half has it and whose Copilot half does not is
correct, because `agent-audit` checks that both halves describe the same job, not
that they match word for word.

**The output-schema rule contradicted itself inside one file.** `contract.md`
said any content only one branch reaches moves to `references/`, and then offered
an "Output format template" body pattern with no qualification. Stated once now,
so it is not re-litigated: an output schema stays in the body only when every flow
produces it and it is roughly 50 words or less. No third option.

**Gotchas tiers disagreed with the script.** `validate.sh` emits the entry count
through `suggest()` and exits 0, while `skill-author` and `skill-audit` both
called more than five entries a FAIL. Whether a given gotcha earns its place is
judgment, so the prose moves to the script's tier rather than the reverse. The
paraphrase rule stays a FAIL and is explicitly marked as the auditor's call — no
script detects it.

**The dispatch exemplar was cited at the wrong number.** `apm-workflow`'s body is
421 words; 554 is its whole-file count. Both `contract.md` and `body-discipline.md`
cited 554 while describing a body budget, so an author calibrating against the
exemplar overshot by ~30% — the exact whole-file/body-only conflation those two
sections exist to warn against, reproduced inside the warning.

**"Error handling" came back as a required body element.** It was one of four and
is the one that gets dropped, and dropping it is not neutral: an agent handed
malformed input with no instruction invents a recovery, and a subagent's invented
recovery is invisible to its caller until the output is wrong. Restored in
`agent-audit`'s rubric as a SUGGESTION, in `agent-author`'s contract and both
scope checklists as a required element, and as an `## Errors` section in all three
templates.

**`skill-author` Step 4 gains the one check the audit misses.** An empty body
reports `PASS SKILL.md body word count 0` — a word gate cannot tell "concise"
from "absent". Step 4 now hand-checks for a non-empty section, and its commit
verification is conditioned on actually being inside a git worktree, which a skill
under `~/.claude/skills/` is not.

Also here: absolute repo paths removed from `skill-author`'s SKILL.md and
contract.md in favour of naming the skill (`zoom-out`'s description is quoted
inline instead of pointed at), the boundary-target universe documented to match
the resolver, a two-hops-from-SKILL.md limit on reference chains, and
`new-agent.sh`'s next-steps output naming the description budget and the
deliberate absence of an agent body gate.

Refs: ADR-0020

plugins/kyberforge/skills/agent-author/assets/templates/claude-code.md

@@ -14,10 +14,14 @@ description: FILL IN: Use when <trigger>. <One capability clause.> Not <thing> -
      boundary clause naming a real sibling skill or agent.
      250 characters is the target, 400 the hard ceiling (ADR-0020).
      Do not open with an action verb ("Reviews...", "Analyzes...") — that rule was
-     deleted. Add "Use proactively" only if the runtime should delegate here without
-     the user naming this agent.
+     deleted.
+     "Use proactively" is valid HERE and only here: it steers the Claude Code runtime
+     to offer this agent unprompted. Add it only if that is what you want. If you add
+     it, leave it OUT of the Copilot half of the pair — the phrase does nothing there
+     and agent-audit's KyberforgeCopilot.ProactivePhrase grades it a hard FAIL. The
+     pair must describe the same job; it does not have to be byte-identical.
      Example: "Use when a diff needs checking for injected credentials before it
-     merges. Not general code review -> code-reviewer." -->
+     merges. Not prose or style linting -> `lint-runner`." -->
 
 <!-- tools: Read, Bash, Grep
      Optional. Allowlist of tool names: a comma-separated string or a YAML list.
@@ -99,3 +103,10 @@ FILL IN: Steps the agent takes. Be specific about ordering if it matters.
 ## Output
 
 FILL IN: What does the agent produce? Format, location, structure.
+
+## Errors
+
+FILL IN: What does the agent do on malformed, missing or contradictory input?
+State whether it stops and reports, or degrades to a named fallback — and what it
+tells the caller either way. An agent with no error handling invents a recovery,
+and an invented recovery is invisible until the output is wrong.