chore(skill): mark 5 heavyweight bundled skills as optional

mateclaw-server/src/main/resources/skills/apple-notes/SKILL.md

@@ -2,6 +2,7 @@
 name: apple-notes
 description: 'Manage Apple Notes via memo CLI: create, search, edit.'
 version: 1.0.0
+optional: true
 platforms:
 - macos
 requires:

mateclaw-server/src/main/resources/skills/blogwatcher/SKILL.md

@@ -2,6 +2,7 @@
 name: blogwatcher
 description: Monitor blogs and RSS/Atom feeds via blogwatcher-cli tool.
 version: 2.0.0
+optional: true
 requires:
 - key: blogwatcher-cli
   type: binary

mateclaw-server/src/main/resources/skills/ckjia-shopping/SKILL.md

@@ -3,6 +3,7 @@ name: ckjia-shopping
 nameZh: 参考价 - 比价购物
 nameEn: CKJIA Shopping
 version: "1.0.1"
+optional: true
 icon: /skill-assets/ckjia-shopping/assets/ckjia_app_icon.png
 description: "跨平台比价与购物推荐 / Cross-platform price comparison. 淘宝 / 京东 / 天猫 / 拼多多商品聚合搜索 + 拍图识物。需要先启用 ckjia-shopping MCP server 并配置 CKJIA_MCP_KEY 才能用。"
 category: data

mateclaw-server/src/main/resources/skills/dingtalk_channel_connect/SKILL.md

@@ -1,6 +1,7 @@
 ---
 name: dingtalk_channel_connect
 version: "1.3.0"
+optional: true
 description: "使用可见浏览器自动完成 MateClaw 钉钉渠道接入。遇到登录页必须暂停等待用户手动登录后继续。"
 dependencies:
   tools:

mateclaw-server/src/main/resources/skills/himalaya/SKILL.md

@@ -1,6 +1,7 @@
 ---
 name: himalaya
 description: "CLI to manage emails via IMAP/SMTP. Use himalaya to list, read, write, reply, forward, search, and organize emails from the terminal. Supports multiple accounts and message composition with MML (MIME Meta Language)."
+optional: true
 dependencies:
   commands:
     - himalaya