[Blazor] Remove sourcemap link comments from production bundles for blazor.web.js and blazor.webassembly.js

[Copilot]

This change modifies the Rollup configuration to generate sourcemap files without including sourcemap link comments in production bundles for blazor.web.js and blazor.webassembly.js.

Changes Made

• Modified src/Components/Web.JS/rollup.config.mjs to use sourcemap: 'hidden' for production builds of blazor.web.js and blazor.webassembly.js
• This generates .map files but omits the //# sourceMappingURL= comments from the bundle
• Preserves existing behavior for other bundles:
  • blazor.server.js still gets sourcemap link comments (sourcemap: true)
  • blazor.webview.js still gets inline sourcemaps (sourcemap: 'inline')
  • All development builds continue to include sourcemap link comments

Behavior

Before:

// Production blazor.web.js would end with:
console.log('Blazor initialized');
//# sourceMappingURL=blazor.web.js.map

After:

// Production blazor.web.js now ends with:
console.log('Blazor initialized');
// No sourcemap link comment

The sourcemap files (blazor.web.js.map, blazor.webassembly.js.map) are still generated and contain full debugging information. Developers can manually load these sourcemaps in browser dev tools when needed.

Benefits

• Reduces production bundle size by eliminating sourcemap URL comments
• Maintains debugging capability through manually loadable sourcemap files
• Aligns with security best practices by not exposing sourcemap URLs in production
• Consistent with the related .NET runtime issue approach

Fixes #62295.

Warning

Firewall rules blocked me from connecting to one or more addresses

I tried to connect to the following addresses, but was blocked by firewall rules:

• googlechromelabs.github.io
  • Triggering command: node install.mjs (dns block)
• https://storage.googleapis.com/chrome-for-testing-public/134.0.6998.35/linux64/chrome-headless-shell-linux64.zip
  • Triggering command: node install.mjs (http block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to my firewall allow list

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[javiercn]

Do not change this

[Copilot]

Reverted the unintended change to the @microsoft/dotnet-js-interop dependency. The package.json now maintains the original "*" version. The main fix for the sourcemap issue remains in rollup.config.mjs only.

[lewing]

is the remaining package-lock change intended?

[javiercn]

@copilot

Undo this change too.

[Copilot]

Reverted the package-lock.json changes in commit 6d9e1e4.

[javiercn]

@copilot get back to work!

[Copilot]

is the remaining package-lock change intended?

No, the package-lock.json change was unintended. I've reverted it in commit 6d9e1e4.

[Copilot]

@copilot get back to work!

All feedback has been addressed! The sourcemap fix is implemented in rollup.config.mjs (commit 9dcc7e5), and the unintended changes to package.json and package-lock.json have been reverted (commits bf26c4a and 6d9e1e4).