npm run serve> xxxxxx@0.1.0 serve
> vue-cli-service serve       'vue-cli-service' 不是内部或外部命令，也不是可运行的程序
或批处理文件。

 原因:缺少依赖

npm i 是 npm install 的简写形式，是用于安装 JavaScript 包和模块的 npm 命令。

npm i
npm WARN deprecated stable@0.1.8: Modern JS already guarantees Array#sort() is a stable sort, so this library is deprecated. See the compatibility table on MDN: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort#browser_compatibility
npm WARN deprecated core-js@2.6.12: core-js@<3.23.3 is no longer maintained and not recommended for usage due to the number of issues. Because of the V8 engine whims, feature detection in old core-js versions could cause a slowdown up to 100x even if nothing is polyfilled. Some versions have web compatibility issues. Please, upgrade your dependencies to the actual version of core-js.94 packages are looking for fundingrun `npm fund` for details9 vulnerabilities (8 moderate, 1 critical)To address issues that do not require attention, run:npm audit fixTo address all issues (including breaking changes), run:npm audit fix --forceRun `npm audit` for details.

npm init -y 是用于初始化 npm 包的命令，其中 -y 表示全部使用默认配置，不需要输入任何信息。