Clarify COPY_VAR layout to show source and destination variables

data/locale/en-US.ini

@@ -1322,6 +1322,7 @@ AdvSceneSwitcher.action.variable.actionNoVariableSupport="Getting variable value
 AdvSceneSwitcher.action.variable.conditionNoVariableSupport="Getting variable values from %1 conditions is not supported!"
 AdvSceneSwitcher.action.variable.currentSegmentValue="Current value:"
 AdvSceneSwitcher.action.variable.layout.other="{{actions}}{{variables}}{{variables2}}{{strValue}}{{numValue}}{{segmentIndex}}{{mathExpression}}{{envVariableName}}{{scenes}}{{tempVars}}{{tempVarsHelp}}{{sceneItemIndex}}{{direction}}{{stringLength}}{{paddingCharSelection}}{{caseType}}{{jsonQuery}}{{jsonQueryHelp}}{{jsonIndex}}"
+AdvSceneSwitcher.action.variable.layout.copy="{{actions}}{{variables2}}to{{variables}}"
 AdvSceneSwitcher.action.variable.layout.pad="{{actions}}of{{variables}}to length{{stringLength}}by adding{{paddingCharSelection}}to the{{direction}}"
 AdvSceneSwitcher.action.variable.layout.truncate="{{actions}}of{{variables}}to length{{stringLength}}by removing characters from the{{direction}}"
 AdvSceneSwitcher.action.variable.layout.substringIndex="Substring start:{{subStringStart}}Substring size:{{subStringSize}}{{subStringRegex}}"

lib/macro/macro-action-variable.cpp

@@ -1633,6 +1633,10 @@ void MacroActionVariableEdit::SetWidgetVisibility()
 		   MacroActionVariable::Action::TRUNCATE) {
 		layoutString = obs_module_text(
 			"AdvSceneSwitcher.action.variable.layout.truncate");
+	} else if (_entryData->_action ==
+		   MacroActionVariable::Action::COPY_VAR) {
+		layoutString = obs_module_text(
+			"AdvSceneSwitcher.action.variable.layout.copy");
 	} else {
 		layoutString = obs_module_text(
 			"AdvSceneSwitcher.action.variable.layout.other");