Fix macOS app half-activation state and menu closure issue

This change has a moderate impact on WebView2Mac. While the modified code involves Remote Cocoa's mouse capture mechanism and menu controller, which are core components that WebView2Mac depends on, the changes primarily affect application-level activation state handling and menu behavior rather than core window bridging functionality. Specific impacts include: (1) Changes in mouse_capture.mm modify the local event monitor's behavior to explicitly activate the app when clicked while inactive. WebView2Mac uses mouse capture functionality through Remote Cocoa to handle user input, and this change may affect click behavior and activation logic for WebView2 controls when the host application is inactive; (2) Changes in MenuCocoaWatcherMac add functionality to ignore a single window key notification. WebView2Mac may use this class to monitor menu state changes, and the new ignore logic could affect menu dismissal timing; (3) MenuController changes affect menu behavior in inactive applications. If WebView2Mac displays context menus or other menus within embedded web content, this change may improve the reliability of menu item execution. Overall, these changes aim to improve user experience by fixing edge cases in activation and menu behavior, and should have a positive impact on WebView2Mac. However, testing is needed to ensure that application activation and menu interactions still work properly in WebView2 scenarios, particularly when users interact with WebView2 controls while the host application is in the background.