Beacon Subprotocol buildout

[acolytec3]

Tracking Issue for Beacon Subprotocol work

• Beacon network light client data types
• Protocol scaffolding
• FindContent flow handling
• LightClientUpdatesByRange handling
• Offer/Accept content gossip
  • Think through gossip logic (currently just offers all content to 5 random nodes)
  • Ensure types match work on this pr
  • Add intelligent handling for LightClientUpdatesByRange
• Lodestar light client integration
  • Happy path syncing from only portal network data
  • Light client sync from Beacon chain - works now using the beaconBridge script
  • Add logic within portalnetwork for bootstrapping light client from sample of lightclient updates retrieved from multiple peers - Add bootstrap retrieval mechanism #460
  • Update optimisticUpdate/finalityUpdate to use signatureSlot as reference slot for requests
• Figure out historicalSummaries and historicalRoots objects and how to store/gossip
• Make typing easier to read and work with
  • Clean up all the (ssz as any)... - solved by Add LightClientForkName enum #475 475
  • Make better handlers for getting content keys creating data
  • Simplify forkdigest logic
• Integrate into CLI and allow initializing light client just from Portal Network data
  • Across the beacon bridge #456 - initial PoC integrating cli
• Integrate into browser client