Allow for the vc to submit its proposer preferences to the network
Co-Authored-By: Eitan Seri-Levi <eserilev@ucsc.edu>
Co-Authored-By: Jimmy Chen <jchen.tc@gmail.com>
Gossip verify and cache bids and proposer preferences. This PR also ensures we subscribe to new fork topics one epoch early instead of two slots early. This is required for proposer preferences.
Co-Authored-By: Eitan Seri- Levi <eserilev@gmail.com>