Build all artifacts in a single MacOS environment

[petertrr]

Thanks for the cross-compilation support, it is possible to build artifacts for all the required platforms from a MacOS machine. This should be used for the release workflow. For the regular CI workflow, a Linux machine should be kept.

As a side task, automatic creation of a Github release should be made optional. Github supports creation of a tag and a release from the Web UI, which is oftentimes more convenient than manual creation of a tag from git.

[lppedd]

Since Kotlin 2.1 it is possible to cross-compile every K/N target from a single host (e.g. Linux), by enabling

kotlin.native.enableKlibsCrossCompilation

https://youtrack.jetbrains.com/issue/KT-71290

[lppedd]

Tested under lppedd#3 btw, seems to work as expected.

You'll have to adjust the publishing step tho.