Add lastRepositoryCheckFailed filter in Admin Area > Projects dashboard

What does this MR do and why?

Add Last repository check failed filter in Admin Area > Projects dashboard.

References

• Part of the bug fix for #567350 (closed)
• Closes #567648 (closed)

Screenshots or screen recordings

Filter selection	Option selection

Scenario	Demo
Set filter to Failed	Screen_Recording_2025-09-16_at_10.19.20_AM
Set filter to No issues	Screen_Recording_2025-09-16_at_10.19.35_AM
Visit url /admin/projects?last_repository_check_failed=1	Screen_Recording_2025-09-09_at_4.16.25_PM

How to set up and validate locally

1. Run the following script to simulate a project with failed check: Project.find(...).update!(last_repository_check_failed: true)
2. Assert UI: Go to /admin/projects and set the filter
3. Assert legacy URL support: Go to /admin/projects?last_repository_check_failed=1.

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.