[consensus] Block Proposers that Send Invalid Blocks

[patrick-ogrady]

If the application returns that a block is actively invalid, we should block the proposer:

monorepo/consensus/src/threshold_simplex/actors/voter/actor.rs

Lines 1908 to 1932 in a7848b5

	verified = verify_wait => {
	// Clear verify waiter
	let context = pending_verify_context.take().unwrap();
	pending_verify = None;
	// Try to use result
	match verified {
	Ok(verified) => {
	if !verified {
	debug!(view = context.view, "proposal failed verification");
	continue;
	}
	},
	Err(err) => {
	debug!(?err, view = context.view, "failed to verify proposal");
	continue;
	}
	};
	// Handle verified proposal
	view = context.view;
	if !self.verified(view).await {
	continue;
	}
	},

[patrick-ogrady]

Related: #3323 (now sufficiently documented)