fix(mobile): rotate pending PR check icons

[iscekic]

Changelog for users

• In-progress and queued pull request check icons now rotate.
• Completed and failed check icons remain static.
• Reduced Motion disables pending icon rotation.

Changelog for maintainers

• Pull request check rows reuse the shared spinning icon for pending states.
• A mounted test protects pending and finished icon behavior.

Changes by area

Pull request checks

Pending checks use the existing motion token and Reduced Motion behavior. Finished checks keep their static status icons.

Test coverage

The mounted check section test verifies rotating pending icons and static success and failure icons.

E2E proof

• Driver checks: 5 checks passed after round 3
• Section mobile-app verification output:
  • mobile: gates cached for c449077 (skipped)
  • mobile-device: 2 shard(s) over 2 device(s): B6F4F8DE-8DBF-41E2-9114-908DADAD1B68 CEB47290-FE68-4B66-9A70-98C3F21E4FFB
  • mobile-device: login probe passed on 2 device(s); app signed in
  • mobile-device: verifier passed
  • mobile-device: spot check clean

The check status list shows the expected icon behavior for each status.

e1-check-statuses.mp4.trim.mp4

Pending check icons rotate while their jobs remain unfinished.

e2-pending-icons-trim.mp4.trim.mp4

Finished check icons remain static after completion or failure.

e3-finished-icons.mp4.trim.mp4

Reduced Motion stops the pending check icon rotation.

e4-reduce-motion-proof.mp4.trim.mp4

Pending check icons rotate during the full device scenario.

e2-pending-icons.mp4.trim.mp4

The check status view respects the Reduced Motion setting.

e1-reduced-motion.mp4.trim.mp4