add Open in Xcode for macOS

[edwinludik]

I (hopefully) added an option "Open in Xcode". Does anyone else maybe have a test environment ready? I will test locally, opening PR to get feedback on the design question.

Design Question: I did not add a second action, using "flutter.xcode.open" for iOS and macOS, should it rather be refactored to use two different actions? Something like ["flutter.xcode.openiOS" and "flutter.xcode.openMacOS"] or ["flutter.xcode.open.iOS" and "flutter.xcode.open.macOS"] or something else?

Missing open MacOS module in xcode #6209

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[stevemessick]

Thanks! Please update AUTHORS if you want credit.

I have not tested it yet but it should be fine. I'll test before the next release.

[edwinludik]

Updated tx @stevemessick - feel free to let me know if you encounter any problems during the testing.

[stevemessick]

@edwinludik Works great, thanks! There is one inconsistency you might want to look into. If you don't have the ios directory open but you have ios selected, then the option is still available. That doesn't happen for macos but probably should. See `OpenInXcodeAction.findProjectFile()' for more details.

I'm planning to ship this as-is, but would be glad to incorporate a fix if you can get it to me in the next four days.

[edwinludik]

I just added a change that I think will fix it?! I don't have a test environment so please let me know. tx!

[stevemessick]

@edwinludik I think you need to open a new PR since this one has already been merged. Thanks!

[stevemessick]

@edwinludik I fixed it in #6851