[material-next][ProgressIndicator] Add LinearProgress component

[lhilgert9]

This issue is to track the work for adding the LinearProgress component to @mui/material-next, moving forward the Material You effort (#29345)

Material You ProgressIndicator specification: https://m3.material.io/components/progress-indicators/overview

Migration Guide steps

• Copy component files from material (v5) to material-next: [material-next][ProgressIndicator] Copy LinearProgress to material next #39779
• Remove deprecated components and componentsProps props: Skipped, no props to remove
• Drop support for ThemeProvider in favor of CssVarsProvider: [material-next][ProgressIndicator] Apply MD3 style to LinearProgress #39807
• Migrate component to Typescript: [material-next][ProgressIndicator] Change LinearProgress files to ts #39793
• Refactor component to use Base UI’s hook if it exists: Skipped, no hooks exists
• Implement Material You design specs: [material-next][ProgressIndicator] Apply MD3 style to LinearProgress #39807
• Add component playground to v5 docs: [material-next][ProgressIndicator] Apply MD3 style to LinearProgress #39807

Note: This comment will be updated to show the progress and list possible issues.

@DiegoAndai

[DiegoAndai]

Completed 🎉