Clear test plugins from public Codex marketplace

Constraint: Public marketplace should only expose production-ready plugins while KeyInfo now publishes internal skills explicitly.
Rejected: Keeping eapil-prefixed test plugins | They conflict with future KeyInfo-published skills and confuse plugin identity.
Confidence: high
Scope-risk: narrow
Directive: Keep plugin IDs stable and avoid eapil-prefixed test fixtures in the public market.
Tested: python scripts/validate_marketplace.py; CODEX_HOME temp codex plugin marketplace add .; CODEX_HOME temp codex plugin add docx@eapil-skill-market
Not-tested: Remote Codex Desktop install after push.

.agents/plugins/marketplace.json

@@ -4,54 +4,6 @@
     "displayName": "EAPIL 技能市场"
   },
   "plugins": [
-    {
-      "name": "eapil-pdf",
-      "source": {
-        "source": "local",
-        "path": "./plugins/codex/plugins/eapil-pdf"
-      },
-      "policy": {
-        "installation": "AVAILABLE",
-        "authentication": "ON_INSTALL"
-      },
-      "category": "文档处理"
-    },
-    {
-      "name": "eapil-pptx",
-      "source": {
-        "source": "local",
-        "path": "./plugins/codex/plugins/eapil-pptx"
-      },
-      "policy": {
-        "installation": "AVAILABLE",
-        "authentication": "ON_INSTALL"
-      },
-      "category": "文档处理"
-    },
-    {
-      "name": "eapil-xlsx",
-      "source": {
-        "source": "local",
-        "path": "./plugins/codex/plugins/eapil-xlsx"
-      },
-      "policy": {
-        "installation": "AVAILABLE",
-        "authentication": "ON_INSTALL"
-      },
-      "category": "数据分析"
-    },
-    {
-      "name": "eapil-threejs",
-      "source": {
-        "source": "local",
-        "path": "./plugins/codex/plugins/eapil-threejs"
-      },
-      "policy": {
-        "installation": "AVAILABLE",
-        "authentication": "ON_INSTALL"
-      },
-      "category": "开发工具"
-    },
     {
       "name": "superpowers",
       "source": {