Implement Windows SysMenu handling

Sine Striker

2024-05-07 e0b59294fc9e9dc8198b8c504860353b6bec0124

 src/core/contexts/win32windowcontext_p.h

@@ -66,11 +66,14 @@

    protected:
        // The last hit test result, helpful to handle WM_MOUSEMOVE and WM_NCMOUSELEAVE.
        WindowPart lastHitTestResult = WindowPart::Outside;
        WindowPart lastHitTestResult;
        int lastHitTestResultRaw;

        // Whether the last mouse leave message is blocked, mainly for handling the unexpected
        // WM_MOUSELEAVE.
        bool mouseLeaveBlocked = false;
        bool mouseLeaveBlocked;

        uint64_t iconButtonClickTime;
    };

}