[TO-DO]. Port over / create an EmbeddedChat component

[Sing-Li]

Either dig into Github history across the three repositories to find the old EmbeddedChat component OR create a new one.

This component should be resizable and placeable and generatable just like any of the other existing compoent, but features "a specific chatroom in a window" ONCE THE USER HAS LOGGED IN VIA THE OIDC component.

WHEN NOT AUTENTICATED -- the behaviour of this component is up to the designer, it can either:

• display a beautifully placed and formatted (across all devices) message that shows the user how to use the OIDC auth to login
• display a chat room that is READ ONLY in real time (with messages scrolling up dynamically, like the old Gitter project) -- basically a specially setup user account that has readonly access to that channel (via RC roles)

The second alternative (login to send messages/participate in the community) is obviously more desirable - but we'll take whatever is functional asap. Thanks.