[WIP] Update template to use Lightning CSS instead of PostCSS

[Copilot]

Migration from PostCSS to Lightning CSS

Changes Completed:

• Update package.json to remove postcss-nesting dependency
• Update package.json to add lightningcss dependency (^1.28.3)
• Update vite.config.js to remove postcssNesting import
• Update vite.config.js to replace css.postcss configuration with Lightning CSS
• Update vite.config.js to add css.transformer: 'lightningcss'
• Update vite.config.js to add css.lightningcss.drafts.nesting: true
• Update vite.config.js to add build.cssMinify: 'lightningcss'
• Test the build process to ensure everything works correctly
• Run code review - no issues found
• Run security scan - no vulnerabilities found

Summary:

All changes have been successfully implemented and validated. Lightning CSS is now configured to handle CSS processing with nesting support and minification.

Original prompt

Objective

Update the template to use Lightning CSS instead of PostCSS for CSS processing.

Changes Required

1. Update package.json

• Remove the postcss-nesting dependency
• Add lightningcss dependency (version ^1.28.3)

2. Update vite.config.js

• Remove the postcssNesting import statement
• Replace the css.postcss configuration with Lightning CSS configuration
• Add css.transformer: 'lightningcss'
• Add css.lightningcss.drafts.nesting: true to enable CSS nesting support
• Add build.cssMinify: 'lightningcss' to use Lightning CSS for minification during builds

Benefits

• Lightning CSS is significantly faster than PostCSS
• Provides built-in support for CSS nesting and other modern CSS features
• Maintains the same CSS nesting functionality previously provided by postcss-nesting

This pull request was created from Copilot chat.

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[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	lightningcss@​1.31.1

View full report