feat: 建立统一目录元数据与获取契约 (#5)

* feat: 建立 Registry 目录元数据验证基础

* feat: 迁移 Registry 应用目录元数据

* test: 解耦目录迁移进度断言

* feat: 迁移 Registry 服务目录元数据

* fix(catalog): 强制 Registry 目录元数据

* fix(catalog): 兼容 Registry v4 外部集成

entries/fetch-mcp/catalog-metadata.v1.json

@@ -0,0 +1,85 @@
+{
+  "$schema": "../../schemas/catalog-metadata.v1.schema.json",
+  "schemaVersion": 1,
+  "identity": {
+    "kind": "service",
+    "id": "fetch-mcp"
+  },
+  "presentation": {
+    "defaultLocale": "zh-CN",
+    "i18n": {
+      "zh-CN": {
+        "name": "Fetch MCP",
+        "summary": "网页内容获取与转换，将网页转为 Markdown 供 LLM 使用"
+      },
+      "en-US": {
+        "name": "Fetch MCP",
+        "summary": "Fetches and converts web content into Markdown for LLM use"
+      }
+    },
+    "tags": [
+      "网页",
+      "抓取",
+      "Markdown"
+    ]
+  },
+  "release": {
+    "state": "known",
+    "version": "2025.4.7",
+    "versionScheme": "calver"
+  },
+  "timestamps": {
+    "catalogUpdatedAt": {
+      "state": "known",
+      "value": "2026-03-09",
+      "precision": "day"
+    },
+    "releasePublishedAt": {
+      "state": "unknown"
+    },
+    "reviewedAt": {
+      "state": "unknown"
+    },
+    "upstreamObservedAt": {
+      "state": "unknown"
+    }
+  },
+  "provenance": {
+    "content": {
+      "kind": "package",
+      "url": "https://pypi.org/project/mcp-server-fetch/"
+    }
+  },
+  "governance": {
+    "availability": "listing-only",
+    "license": {
+      "state": "unknown"
+    },
+    "redistribution": "verify-package-terms",
+    "upstreamMaintainer": {
+      "name": "Anthropic",
+      "verified": false
+    }
+  },
+  "compatibility": {
+    "platforms": {
+      "state": "known",
+      "values": [
+        "macos",
+        "windows",
+        "linux"
+      ]
+    }
+  },
+  "spec": {
+    "kind": "service",
+    "protocol": "mcp",
+    "authType": "unknown",
+    "capabilities": [
+      "url_fetch",
+      "html_to_markdown",
+      "content_extract"
+    ],
+    "toolCount": 1
+  }
+}