Tabs now have IDs, and we use those IDs to open things. This doesn't do any conversion to typescript, and doesn't add the same feature to the room settings out of concern for the size of diff.
Like a5f3318f3b, this proves that the new dispatcher conversion works for fire-and-forget style dispatches too. This is another obvious-if-broken and generally safe conversion to make.
Other actions which can be dispatched this way have been excluded for reasons mentioned in the Action enum's comments.
This is a relatively obvious dispatch action that doesn't require a lot of complicated type definitions, so should be a good candidate to prove the thing works. If for some reason the thing stops working, we've done something wrong.
This also adds a bit of generic types to the dispatch call so we don't confuse the tsx parser by using `dis.dispatch(<ViewUserPayload>{...})` as it thinks that's supposed to be a component. We still get type safety, and the thing remains happy with the generics approach.
