[4.0] Add support of iOS's dynamic libraries to GDNative

[naithar]

Same as #39996.

Since iOS platform is not buildable at master at the moment, I've managed to test only library selection in editor.

For iOS platform it is not allowed by AppStore to use .dylib directly, so not loading them at this moment makes sense.
But since the release of iOS 8 developers are allowed to use Frameworks, which essentially are dylibs packed with Info.plist file and additional install_name value set to them.

Because of that .dylibs can be replaced with .framework or .xcframework files built with XCode. They can also be turned into .framework automatically. This way the dynamic library loading will be available for iOS platform.

This repo contains the starter project, allowing the creation of .a, .dylib, .framework or .xcframework, which could be used for GDNative library in project.

I've tested this PR with both statically and dynamically linked libraries in different combinations, running on multiple devices that's available to me.
I've also tested the way .framework generation works and how AppStore handles resulting application.
I haven't found any issues, but I could have missed some edge case.

[akien-mga]

Thanks!