fix(zscript): stale data in destructors

scripted objects weren't clearing data used by the destructor when being cleared, leading to future objects referencing the stale data if they didn't have a destructor of their own to overwrite it.

src/user_object.cpp

@@ -204,6 +204,7 @@ void user_object::clear_nodestruct()
 	data.clear();
 	reserved = false;
 	owned_vars = 0;
+	destruct.clear();
 }
 void user_object::clear()
 {