fix(vite): add configured headers for devtool-related response

[nighca]

server.headers in vite configuration is now ignored by __devtool__ related requests, which are handled by sirv.

This PR applies server.headers in vite configuration to these requests' response.

This PR fixes #565.

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[pkg-pr-new]

Open in Stackblitz

@vue/devtools-applet

pnpm add https://pkg.pr.new/@vue/devtools-applet@710

@vue/devtools-core

pnpm add https://pkg.pr.new/@vue/devtools-core@710

@vue/devtools

pnpm add https://pkg.pr.new/@vue/devtools@710

@vue/devtools-api

pnpm add https://pkg.pr.new/@vue/devtools-api@710

@vue/devtools-kit

pnpm add https://pkg.pr.new/@vue/devtools-kit@710

vite-plugin-vue-devtools

pnpm add https://pkg.pr.new/vite-plugin-vue-devtools@710

commit: 5294d4b

[webfansplz]

@nighca I tested this with use case #565, but the issue still seems to exist. You can reproduce it with pnpm run build && pnpm run play

[nighca]

@nighca I tested this with use case #565, but the issue still seems to exist. You can reproduce it with pnpm run build && pnpm run play

@webfansplz The issue is fixed as I confirmed by following these steps:

1. Checkout code from my branch: https://github.com/nighca/vuejs-devtools/tree/fix-devtool-header

2. Configure packages/playground/basic/ with Cross-Origin-* headers:

   server: {
     port: 3000,
     headers: {
       'Cross-Origin-Embedder-Policy': 'require-corp',
       'Cross-Origin-Opener-Policy': 'same-origin',
     },
   },

3. Run pnpm run build && pnpm run play and open http://localhost:3000. The devtool page can loads correctly.

4. Checkout branch main

5. Run pnpm run build && pnpm run play and open http://localhost:3000. Now the devtool page fails to load, showing "localhost refused to connect."

While during testing, I noticed that sometimes the script (pnpm run build && pnpm run play) did not update the built result (packages/vite/dist/vite.mjs) as expected, likely due to build caching. This may explain why you still encountered the "devtool-failed-to-load" issue. You may check the content of packages/vite/dist/vite.mjs to verify.