macos-13 was retired by GitHub in December 2025 and no longer works.
Intel-based macOS runners are being phased out entirely by GitHub,
with only expensive *-large variants remaining as alternatives.
Closes#387
Made-with: Cursor
* try to fix failing tests
* continue on error
* remove Flutter versions that aren't available natively for arm64 macOS
* explicitly specify arch = x64 (`-a x64`)
* fix order of args
* remove redundant quotes
* make `dry-run` also accept bools
* update README with new info
* setup.sh: update arg parsing to add support for `flutter-version-file` as `-f pubspec.yaml`
* action.yaml: add flutter-version-file
* setup.sh: require `yq` only when -f option is specified
* fix tests and add a new one
* enable shell options: `errexit` and `nounset`
* move falling back to defaults to single place - setup.sh
* action.yaml: reduce number of arguments in the last invocation
