feat(optimizer): add rush lockfile support

[Copilot]

• Analyzed the issue: Vite's dependency optimizer assumes hardcoded lockfile locations, making it incompatible with Rush.js monorepos
• Reviewed current implementation in packages/vite/src/node/optimizer/index.ts
• Understood getLockfileHash function and lockfileFormats array
• Built and linted the project to establish baseline
• Add support for detecting Rush.js lockfiles automatically by adding .rush/temp/shrinkwrap-deps.json to lockfileFormats
• Remove all other changes per maintainer feedback - keep only the Rush.js lockfile format addition
• Reposition Rush.js lockfile entry to be right after pnpm lockfile entry for better organization
• Run linting and build to ensure changes work properly
• Verify all existing tests still pass

Implementation Details

Rush.js Lockfile Support

Added Rush.js lockfile format to the lockfileFormats array to enable automatic detection of .rush/temp/shrinkwrap-deps.json files. The entry is positioned right after the pnpm lockfile entry since Rush.js uses pnpm internally.

This minimal change resolves the core issue where Vite fails to work with Rush.js monorepos due to non-standard lockfile locations, without adding any new configuration options.

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Additional instructions:

Add the code to optimizer/index.ts

Fixes #20817

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[bluwy]

I wonder if we should also uncomment this if we somewhat have rush support now:

vite/packages/vite/src/node/server/searchRoot.ts

Line 13 in 4a40a8e

// 'rush.json',

It was added in https://github.com/vitejs/vite/pull/2850/files#diff-64df9f2b7e879d5f5da8a632345e240f078cbb36a258ec5c92752744d02a87c9R13

[sapphi-red]

I think we can add that too (maybe also with nx #20090). But I guess we should add it in a major because it will allow more files in fs.strict.