Mitchell Hashimoto 2caa8a3fe1 macOS: move window title handling fully to AppKit
Fixes #7236
Supersedes #7249

This removes all of our `focusedValue`-based tracking of the surface
title and moves it completely to the window controller. The window
controller now sets up event listeners (via Combine) when the focused
surface changes and updates the window title accordingly.

There is some complicated logic here to handle when we lose focus to
something other than a surface. In this case, we want our title to be
the last focused surface so long as it exists.
2025-05-06 14:57:19 -07:00
..