Calculate PartyData (score, missing items, etc.) on client instead of server

[Nasicus]

We are already calculating a lot of the stuff already on the client (missing items).
Plus it would take the work away from the server which is in this case good.

However currently this is done in the table component on "render" (I think). We'd need to move this out somewhere, maybe to the GrailManager?

Before implementing this we should first discuss how we want to do it.