Make the user search automatically. This includes a timer to ensure that we aren't constantly pinging the server as the user types, the search is started 0.5s after the user stops typing. The `PublicRoomListModel` is upgraded to work in the same manner as it was architected slightly differently.
Pull the generic aspects from Room search and join room pages into it's own component. This is done in anticipation of using the new generic search page for a user search functionality.
- `SearchPage` is now used for the generic version with the old one being renamed `RoomSearchPage`
- `JoinRoomPage` is renamed to `ExploreRoomsPage` inline with everywhere else in NeoChat
There is also some cleanup of the code for both search pages in here.
