feat(p2p): implement p2p sync

[cchudant]

supersedes and closes #400

Pull request description will be added later

[cchudant]

Here is my TODO list as of now:

• Fix peer spamming when low peer count (add timeout per peer in peerset)
• Debug sync from pathfinder/juno of around ~10k blocks
• Follow the latest L1 block instead of the temporary unbounded syncing thing
• Re-add gateway sync mode
  • Tidy: remove mc_block_import
  • Tidy: remove mc_sync, replace it with the new mc_sync2
  • Tidy: cli args for mc_sync
  • Pending block shenanigans
  • Save sync tip to db, db flushing
• Rebase work on latest main
• Mark this pull request as ready.
• Merge p2p in experimental state :)

After this pr is merged, I would open further PRs for:

• fix: bubble up low level p2p errors so that we can punish the peer in peerset
• fix: pre-v0.13.2 block hash computation
• fix: nicer logging and data collection
• fix: sync_handlers response should not follow chain
• feat: signature verification
• feat: backward sync
• feat: Block propagation
• feat: Transaction propagation
• fix: p2p relay circuit
• fix: "syncing" jsonrpc endpoint
• code quality: remove optional commitments in block headers primitives