Stacker liveness enforcement in the stacks-node

[kantai]

The stacks-node will take the signer participation bit vectors as a given from the signer set (#4241), but it does need to implement the punishment for non-participation. As discussed in the SIP, this should take the form of losing PoX rewards, but the exact design of this still needs to be designed and implemented.

Because it impacts a block-commit's outputs, this means that block-commits cannot be validated without the data that goes into the punishment (the prior stacks block's bit vectors).

[AshtonStephens]

Depends on info from discussion #4195

[kantai]

This should be implemented with the minimal consensus impact: the bitvec should be enforced on the next block (i.e., the sortition can do a single look back for discovering punishment).