virtual-keyboard: destroy on vdestroy event

src/helpers/WLClasses.hpp

@@ -7,6 +7,7 @@
 #include "../desktop/Popup.hpp"
 #include "AnimatedVariable.hpp"
 #include "../desktop/WLSurface.hpp"
+#include "signal/Listener.hpp"
 #include "Region.hpp"
 
 class CMonitor;
@@ -92,6 +93,10 @@ struct SKeyboard {
 
     void                 updateXKBTranslationState(xkb_keymap* const keymap = nullptr);
 
+    struct {
+        CHyprSignalListener destroyVKeyboard;
+    } listeners;
+
     // For the list lookup
     bool operator==(const SKeyboard& rhs) const {
         return keyboard == rhs.keyboard;