Fix agent stale session (#1551)

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Fixes OPS-2961

Author: alexandrudanpop

packages/react-ui/src/app/features/ai/lib/assistant-ui-chat-hook.ts

@@ -129,10 +129,14 @@ export const useAssistantChat = ({
           stepDetails &&
           flowId
         ) {
+          const stepId =
+            flowHelper.getStep(context.flowVersion, context.selectedStep)?.id ??
+            context.selectedStep;
+
           return await aiChatApi.open(
             flowId,
             getBlockName(stepDetails),
-            context.selectedStep,
+            stepId,
             getActionName(stepDetails),
           );
         }
@@ -292,7 +296,11 @@ export const useAssistantChat = ({
 
       if (oldChatId) {
         const context = getBuilderState();
-        if (context?.selectedStep && context?.flowVersion) {
+        if (
+          context?.selectedStep &&
+          context?.flowVersion &&
+          chatMode === ChatMode.StepSettings
+        ) {
           await aiChatApi.delete(oldChatId);
           chat.setMessages([]);
         } else {
@@ -308,7 +316,7 @@ export const useAssistantChat = ({
         `There was an error canceling the current run and invalidating queries while creating a new chat: ${error}`,
       );
     }
-  }, [chatId, chat, onChatIdChange, getBuilderState]);
+  }, [chatId, chat, getBuilderState, chatMode, onChatIdChange]);
 
   return {
     runtime,