Add notifications and indicators for party invites similar to that of chat messages

<img width="719" height="84" alt="Image" src="https://github.com/user-attachments/assets/9d532b99-55da-43a7-9275-b4143e42b3f8" />

Notifications are possible via `chotify`, should be easy.
The indicator like with unread chat messages I'm not sure, probably needs a bit of investigation.