fix(borders): respond to sys foreground winevent w/ border manager event

This commit ensures that we emit a dedicated border manager event when
WinEvent::SystemForeground is received.

The OS can actually be slower than komorebi when it comes to processing
changed focus state, and in the border manager we rely on
GetForegroundWindow when calculating which the border focus state and
color should be.

This has previously resulted in a situation where there may be no border
with the "focused" color.

This should no longer be a problem because even in the situations where
the OS is slower than komorebi and is still returning an old HWND from
GetForegroundWindow, the new event that we emit to border manager in
response to WinEvent::SystemForeground will ensure that the border focus
colors get updated.

komorebi/src/windows_callbacks.rs

@@ -115,6 +115,16 @@ pub extern "system" fn win_event_hook(
         }
     }
 
+    // sometimes the border focus state and colors don't get updated because this event comes too
+    // slow for the value of GetForegroundWindow to be up to date by the time it is inspected in
+    // the border manager to determine if a window show have its border show as "focused"
+    //
+    // so here we can just fire another event at the border manager when the system has finally
+    // registered the new foreground window and this time the correct border colors will be applied
+    if matches!(winevent, WinEvent::SystemForeground) && !has_filtered_style(hwnd) {
+        border_manager::send_notification(Some(hwnd.0 as isize));
+    }
+
     let event_type = match WindowManagerEvent::from_win_event(winevent, window) {
         None => {
             tracing::trace!(