Fyne package should optionally pad icons for Mac OS to fit conventions

[dweymouth]

Checklist

• I have searched the issue tracker for open issues that relate to the same feature, before opening a new one.
• This issue only relates to a single feature. I will open new issues for any other features.

Is your feature request related to a problem?

On Mac OS, application icons are supposed to have a small amount of transparent padding around the main icon image (this is to allow for icons that have a "tool" like the hammer in the XCode icon that extend beyond the main image's rounded rectangle). See here and here for more info.

Is it possible to construct a solution with the existing API?

No response

Describe the solution you'd like to see.

It would be nice for fyne package to be able to automatically add the standard amount of padding around the input icon when packaging for Mac OS. This should be optional/disableable in case the developer has already prepared an icon asset that is directly suitable for Mac OS.

[andydotxyz]

Should we add the curved corner as well? This happens automatically on iOS apps...

[dweymouth]

Should we add the curved corner as well? This happens automatically on iOS apps...

Yes that would be nice too. Of course it should be disableable/optional as well. I manually rounded corners for my icon (and it's rounded on Linux/Windows too) but I had to prepare a mac-specific padded version.

[andydotxyz]

Fixed on develop :)