transport: Change AddressStore to keep track of more dial addresses

[lexnv]

The address store keeps track of the addresses of peers, sorted internally by connection scores.
Once an address is inserted into the store, its score can never change.

We are currently losing track of dialed addresses if we already have a dial inflight:

• fn dial_addresses(address: Multiaddr) helps us learn about a peer multiaddress
• we completely discard the address if the peer is already Dialing Connected or Opening

Instead, we could keep track of the address:

• insert it into the store, if not already present with score 0 (zero)
• when we receive a successful / failure event -> update the reputation of the address (this is not present atm)
• this should help us lower the reputation of addresses that fail to respond over multiple attempts

A few other thoughts to look over:

• Here the store returns a sorted by score list of addresses. We collect them to a hashmap, which when iterated doesn't preserve the order of elements.
  

  litep2p/src/transport/manager/mod.rs

  Lines 453 to 457 in 443f05c

  	let mut records: HashMap<_, _> = addresses
  	.take(self.max_parallel_dials)
  	.into_iter()
  	.map(|record| (record.address().clone(), record))
  	.collect();

• The following should be changed as it is redundant

litep2p/src/transport/manager/handle.rs

Lines 194 to 196 in 443f05c

	for record in addresses {
	if !context.addresses.contains(record.address()) {
	context.addresses.insert(record);

litep2p/src/transport/manager/address.rs

Lines 204 to 209 in 443f05c

	/// Insert new address record into [`AddressStore`] with default address score.
	pub fn insert(&mut self, mut record: AddressRecord) {
	if self.by_address.contains(record.address()) {
	return;
	}

• Limit the number of known connections (maybe 16 would be a good start)

Tasks

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1. address_store: Improve address tracking and add eviction algorithm #250
   enhancement +1
   

[lexnv]

Closed by #250