ci: switch macos runners to cirrus

[HayesGordon]

No description provided.

[mfazekas]

I have kind of a mixed experience with cirrus in this PR:

1. macos-runner:sonoma with Xcode 16.1 works when runners are available, but availability is unpredictable - sometimes starts in 2-3 min (https://github.com/rive-app/rive-nitro-react-native/actions/runs/21033363934), sometimes stays queued 20+ min (https://github.com/rive-app/rive-nitro-react-native/actions/runs/21058093701).
2. Other images (macos-runner:sequoia, macos-sequoia-xcode:16.4) with Xcode 16.4 never start - they stay queued indefinitely. (https://github.com/rive-app/rive-nitro-react-native/actions/runs/21030264666)