chore(apm): give bin a published description that describes it

Why: bin's marketplace description read "A place for things to be binned" — a
routing boundary sitting in the enumeration slot, phrased as a joke. It is what
a consumer sees in the marketplace listing for a plugin shipping eleven
substantive skills: research, write-docs, tdd, prototype, triage, diagnose,
improve-codebase-architecture, grill-me, grill-with-docs, zoom-out and caveman.

This is the same category error b0ef503 fixed for git and gitea, and the same
text bb9158d moved out of core's description in August — "triage, diagnosis,
architecture review" left core precisely because those skills live in bin, so
bin is where it should have landed.

Implementation notes: bin 1.1.3 -> 1.1.4, marketplace 0.4.3 -> 0.4.4, PATCH for
metadata under the per_package strategy. README's bin line mirrors the new
description. architecture.md's routing boundary is deliberately left as
"unsorted skills that have not earned a home yet" — that is still true, and it
answers a different question than the listing does.

Impact: consumer-facing. apm-pack-check-clean, check-plugin-content-sync,
check-marketplace-mirror-sync, validate-marketplace, validate-plugins and
apm-audit-ci all pass.

apm.yml

@@ -52,7 +52,7 @@ marketplace:
   # top-level apm.yml description:/version: above are NOT inherited into the
   # compiled output despite being used elsewhere (e.g. by `apm audit`).
   description: AI development skills for Claude Code and GitHub Copilot CLI — factory, design, implement, review, and cross-cutting workflows.
-  version: 0.4.3
+  version: 0.4.4
   owner:
     name: Defame1297
     email: defame1297@rkdr.net
@@ -83,9 +83,9 @@ marketplace:
       category: Developer Tools
 
     - name: bin
-      description: A place for things to be binned
+      description: Cross-cutting workflow skills not yet split into a focused plugin — research, documentation, TDD, prototyping, triage, diagnosis, architecture review, and requirement grilling.
       source: ./plugins/bin
-      version: 1.1.3
+      version: 1.1.4
       category: Utilities
 
     - name: git