feat: `Event::Reopen` support for macOS

[I-Info]

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

Description

This event is typically used to handle dock icon clicking event on macOS and uses applicationShouldHandleReopen:hasVisibleWindows: callback from AppKit Framework.

Use case

It will make it possible to keep application running in backgound when all windows are closed, and create new window after dock icon clicked (application reopen callback).