Cirrus CI Shutdown

According to https://cirruslabs.org/
> [Cirrus CI](https://github.com/cirruslabs/cirrus-ci-docs) will shut down effective Monday, June 1, 2026.

As even the domain seems completly gone, a new provider for running the apple silicon ci is necessary.

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See [.cirrus.yml](https://github.com/chakra-core/ChakraCore/blob/master/.cirrus.yml)

Start with .cirrus.yml and determine how the current Apple silicon CI jobs are configured. Research a replacement provider and define the required configuration changes; done means the project’s Apple silicon CI runs successfully after Cirrus CI is unavailable.

Written by the indexing model from the issue text.