add build workflows

[bdlukaa]

Pre-launch Checklist

• I have updated CHANGELOG.md with my changes
• I have run "dart format ." on the project
• I have added/updated relevant documentation

[h3x4d3c1m4l]

lmk if you would like any help with macOS!

[bdlukaa]

I don't think it makes sense to have a build workflow for platforms other than windows

[h3x4d3c1m4l]

Well looking from "Microsoft perspective", it probably doesn't cause Fluent UI is designed for Windows. However, due to Flutter's nature being a multiplatform UI framework, it could make sense. There is nothing in fluent_ui that stops me from running my fluent_ui based apps on macOS. It even looks pretty nice too 😄

On the other hand there are pretty good reasons you could indeed ignore other platforms:

• As of now you still need macOS to compile for macOS, and macOS minutes on GH Actions are expensive
• You do not own a mac currently, thus maintenance would be community based

[bdlukaa]

I ended up adding the build workflow for it, just for precaution.

As of now you still need macOS to compile for macOS, and macOS minutes on GH Actions are expensive

They aren't charged on public repos