fix(@aether/editor-host): 声明 Vercel 输出目录与构建命令

[devin-ai-integration]

Summary

针对 Vercel 报错 No Output Directory named "dist" found，为 editor-host 增加显式项目配置：

{
  "framework": "vite",
  "buildCommand": "pnpm run build",
  "outputDirectory": "dist",
  "installCommand": "pnpm install --frozen-lockfile"
}

该配置应与 Vercel Project Settings 的 Root Directory apps/@aether/editor-host 配套使用，避免平台在 monorepo 根目录寻找错误的 dist 路径或使用未预期的构建命令。

验证：在 editor-host 目录执行 VERCEL=1 pnpm run build，成功生成 dist/index.html 与静态 assets。

Link to Devin session: https://app.devin.ai/sessions/7e670767e05f493aa100328490d2a1b8
Requested by: @CodeSky-dev

[devin-ai-integration]

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