feat(x11): Add Window::drag_resize_window

[mmstick]

• Tested on all platforms changed
• Added an entry to CHANGELOG.md if knowledge of this change could be valuable to users
• Updated documentation to reflect any user-facing changes, including notes of platform-specific behavior
• Created or updated an example program if it would help users understand this functionality
• Updated feature matrix, if new features were added or implemented

Implements functionality required to resolve #725 for X11. Uses the example from #2003. Only supports X11 on Linux for now. Wayland support will require a future release of sctk with the additional protocol added to the API. And there's some substantial changes in sctk at the moment so upgrading this library will be a bit of a chore. Code from #2003 for Windows support could be added on top of this.

[aniketbiprojit]

Winit supports drag_window_resize without any addition in current master on Apple M1. Probably shouldn't panic on drag_window_resize and just give a warning to developers.

Screen.Recording.2022-10-16.at.8.19.22.PM.mov

[mmstick]

There isn't a panic in the source code. It is simply stating that it's not supported by winit Err(NotSupported). The application you compiled is unwrapping the error, causing a panic. This patch only adds support for X11. I don't have a Mac to add support for that.

[aniketbiprojit]

Cool. Just wanted to add that Apple supports this out-of-the-box right now without calling this function.

[kchibisov]

You should remove the parts saying that Wayland is impelemented since it's cleary not.

[mmstick]

Which parts mention that Wayland is supported? I did already update the platform-specific table to only show that X11 is supported.

[kchibisov]

Looks fine, just some minor notes.

[mmstick]

Rebased with conflicts resolved. The period added to the changelog entry.

[kchibisov]

Thanks, I somehow forgot that this PR existed.