refac: play sound only in last active tab

src/lib/stores/index.ts

@@ -69,7 +69,7 @@ export const temporaryChatEnabled = writable(false);
 export const scrollPaginationEnabled = writable(false);
 export const currentChatPage = writable(1);
 
-
+export const isLastActiveTab = writable(true);
 export const playingNotificationSound = writable(false);
 
 export type Model = OpenAIModel | OllamaModel;