We have added missed blocks to the validator monitor: sigp/lighthouse#4731

I didn't look but assume this also made it to the API (if it didn't we can add it to the API for Siren).

We should also know when we propose a block.

We should currently add alerts for these.

Missed blocks and proposed blocks could also be added into the validator information page.

We could also get attestations sent from the logs and these could also be added. Potentially the same with the aggregated attestations.