fix(agent-audit): remove user-invocable as a hand-invoked marker

disable-model-invocation and user-invocable are independent Copilot
fields: the first gates whether the runtime auto-selects an agent (i.e.
whether its description is a routing string), the second only gates
manual invocation. An agent can be disable-model-invocation: false plus
user-invocable: false and still be model-routed, so the old bullet
conflated two unrelated contracts under one trigger.

Fixes: #125
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EeH8SCbcrCAQrtymkNuhKP

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

@@ -27,15 +27,19 @@ where the body's flowchart specified two.
 
 Read the frontmatter before judging a single word.
 
-- **`disable-model-invocation: true` or `user-invocable: false`** — 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. Both fields are Copilot-only and neither
-  is 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.
+- **`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: it only blocks manual invocation and is
+  independent of `disable-model-invocation` — an agent can be `user-invocable: false` and still
+  model-routed, in which case the three-part shape below still applies. It 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