Checklist:

• I have read and followed the contribution guidelines.
• I have read and followed the how to open a pull request guide.
• My pull request targets the main branch of freeCodeCamp.
• I have tested these changes either locally on my machine, or GitHub Codespaces.

Closes #67770

Summary

This PR fixes an accessibility regression in the Learn UI where course progress was no longer conveyed to screen reader users.

Prevously, screen reader users could understand progress for a lesson or block, but after the recent UI changes the progress bar became effectively visual-only. This update adds accessible progress semantics so assistive technologies can announce the course progress again.

Changes

• add role="progressbar" to the course progress UI
• add aria-label using the block title and progress meta text
• add aria-valuemin, aria-valuemax, aria-valuenow, and aria-valuetext
• add tests to verify progress is exposed to screen readers in both standard and minified modes