[p2p] Remove `max_peer_set_size`

[patrick-ogrady]

Instead of requiring the user to provide a max_peer_set_size (

monorepo/p2p/src/authenticated/discovery/config.rs

Lines 97 to 101 in 877d871

	/// Maximum number of peers to track in a single peer set.
	///
	/// This is used to limit the size of the bit vec messages, which will take one bit per peer in
	/// the set. This number can be set to a reasonably high value that we never expect to reach.
	pub max_peer_set_size: u64,

), we should add an "index" to BitVec messages that can be partially read to determine the size of a set (if we know about it).

This should avoid the error-prone specification of this value (and avoid unnecessary BitVec handling).