fix issue#762: upon clicking to resend, the conversation content is cleared.

If there is no subsequent message or if the next message is from the user, this message should be resent. delete the old message after processing is complete.

src/renderer/src/pages/home/Messages/MessageMenubar.tsx

@@ -96,9 +96,9 @@ const MessageMenubar: FC<Props> = (props) => {
       })
     }
 
-    if (!nextMessage) {
-      onDeleteMessage?.(message)
+    if (!nextMessage || nextMessage.role === 'user') {
       EventEmitter.emit(EVENT_NAMES.SEND_MESSAGE, { ...message, id: uuid() })
+      onDeleteMessage?.(message)
     }
   }, [assistantModel?.id, message, model?.id, onDeleteMessage, onGetMessages])