CI workflows blocked by missing self-hosted runners

[xMinhx]

The current CI workflow is configured to use self-hosted runners, but no runner is available in the repository environment.
As a result, pull request checks stay stuck and older PRs cannot be validated.

Suggested fix:

• Switch the workflow jobs to ubuntu-latest
• Keep the existing job structure and conditions where possible
• Make sure PR checks run again on the hosted GitHub runners

Expected result:

• PR checks execute successfully again
• Existing open PRs can be validated and merged in a normal order