Hide the mouse when the user is typing in the editor - take 2 (#27519)

Closes #4461

Take 2 on https://github.com/zed-industries/zed/pull/25040. 

Fixes panic caused due to using `setHiddenUntilMouseMoves` return type
to `set` cursor on macOS.

Release Notes:

- Now cursor hides when the user is typing in editor. It will stay
hidden until it is moved again. This behavior is `true` by default, and
can be configured with `hide_mouse_while_typing` in settings.

---------

Co-authored-by: Peter Tripp <peter@zed.dev>
Co-authored-by: Thomas Mickley-Doyle <thomas@zed.dev>
Co-authored-by: Agus <agus@zed.dev>
Co-authored-by: Kirill Bulatov <kirill@zed.dev>
Co-authored-by: Agus Zubiaga <hi@aguz.me>
Co-authored-by: Angelk90 <angelo.k90@hotmail.it>

crates/gpui/src/platform.rs

@@ -1228,6 +1228,9 @@ pub enum CursorStyle {
     /// A cursor indicating that the operation will result in a context menu
     /// corresponds to the CSS cursor value `context-menu`
     ContextualMenu,
+
+    /// Hide the cursor
+    None,
 }
 
 impl Default for CursorStyle {