docs(skill): 修正工具 output 契约——必须声明 render

[liyubin117]

当前生成的插件会报错，导致无法正常启动

file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/dsh-app-boot/lib/index.js:1187
                throw new Error(`${binName}: ${stage}: ${detail}${stack}`, { cause });
                      ^

Error: dsh: plugin tree failed to load: failed to apply loader entry dsh-hello (dsh-hello): tool "hello_tool" must declare output { schema, render, presentationMeta? }
TypeError: tool "hello_tool" must declare output { schema, render, presentationMeta? }
    at Proxy.register (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/dsh-tools/lib/index.js:2765:188)
    at Object.apply (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:120:36)
    at new apply (file:///Users/elvin.li/Documents/dsh_workspace/dsh-hello/index.mjs:19:13)
    at Fiber.execute (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:1067:24)
    at file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:1141:34
    at file:///Users/elvin.li/.dsh/profiles/web/#dsh-hello
    at file:///Users/elvin.li/.dsh/profiles/web/#include
    at boot (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/dsh-app-boot/lib/index.js:1187:9)
    at process.processTicksAndRejections (node:internal/process/task_queues:105:5)
    at async runProfile (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/lib/profile-boot-DG5t9aNs.js:247:14)
    at async file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/lib/bin.js:133:3 {
  [cause]: Error: failed to apply loader entry dsh-hello (dsh-hello): tool "hello_tool" must declare output { schema, render, presentationMeta? }
      at updateError (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis-plugin-loader/lib/index.js:299:9)
      at Entry._await (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis-plugin-loader/lib/index.js:506:10)
      at async Promise.allSettled (index 147)
      at async Proxy.await (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis-plugin-loader/lib/index.js:182:22)
      at async boot (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/dsh-app-boot/lib/index.js:1177:3)
      at async runProfile (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/lib/profile-boot-DG5t9aNs.js:247:14)
      at async file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/lib/bin.js:133:3 {
    [cause]: TypeError: tool "hello_tool" must declare output { schema, render, presentationMeta? }
        at Proxy.register (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/dsh-tools/lib/index.js:2765:188)
        at Object.apply (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:120:36)
        at new apply (file:///Users/elvin.li/Documents/dsh_workspace/dsh-hello/index.mjs:19:13)
        at Fiber.execute (file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:1067:24)
        at file:///opt/homebrew/lib/node_modules/@deepseek-ai/dsh/node_modules/@deepseek-ai/cordis/lib/index.js:1141:34
        at file:///Users/elvin.li/.dsh/profiles/web/#dsh-hello
        at file:///Users/elvin.li/.dsh/profiles/web/#include
  }