View account roles across all chains #16

The account view is currently scoped to one chain, but accounts can have roles on multiple chains and it makes sense to want to see all of them at once. Like how Zapper displays assets across all chains. With AccessControlCrossChain this is particularly relevant.

This may be simpler to implement with an upcoming version of @urql/svelte so we may want to wait for that (urql-graphql/urql#2370).