Is your feature request related to a problem? Please describe. swift-libp2p currently doesn't compile on Linux (64bit Ubuntu specifically)

Describe the solution you'd like ensure swift-libp2p and all of it's dependencies can compile on Linux (at least 64bit, 32bit arm would be cool too)

Describe alternatives you've considered n/a

Additional context I think at the moment the primary blocker is swift-libp2p-crypto/issues/2.

This PR...

Fixes:

• When using Swift 5.4 (and SPM 5.4) we receive a Package resolution error stating the product SwiftProtobuf can't be found in the package swift-protobuf.
• This issue happens when packages specify a different Package.name property compared to the GitHub repo name.

By:

• Explicitly declares the SwiftProtobuf package name in the Package.swift file

This PR introduces...

• A new Connection implementation (ARCConnection)
  • ARCConnections are an attempt at creating a Connection that closes itself after a given idle time
  • Idle being 0 active Streams open within the idle grace period (250ms to start)
• An updated ConnectionManager
  • Ability to force close / prune active connections when we're at our max connection limit.
  • Implemented a buffer zone where outgoing connections are allowed while incoming connections aren't
  • Better connection history logging
• An updated PeerStore
  • Ability to prune peers once we reach the maximum peer amount
  • Ability to compact peerstore records
• API Change from ResponseType to Response

/// OLD
host.routes.on("echo", "1.0.0") { req -> ResponseType<ByteBuffer> in ... }

/// NEW
host.routes.on("echo", "1.0.0") { req -> Response<ByteBuffer> in ... }

• Identify Protocol Improvements
• General bug fixes

Multiple Servers

Updated the Application+Servers storage to support multiple servers. The Server protocol now enforces a static Key that prevents multiple servers of the same type from being instantiated and installed on the app at the same time.

Installing/registering servers works via

app.servers.use(.tcp)
/// or with the listen shortcut
app.listen(.ws(host: ..., port: ...))

You can access a specific transports server via

app.servers.server(for: TCPServer.self)

Note: The serve command needs some TLC to reflect the multiple server use case now.

Note: This hasn't been extensively tested. But seems to work internally (swift-swift) and externally with (swift-go) & (swift-js).

Describe the bug The DefaultConnectionManager introduced Stream Counting on Connections in order to close connections who are idle with zero streams. The ConnectionStreamCount dictionary entry isn't always being removed with removed connections. After running the DHT for 12 hours you can see the leak in the number of entries vs the active connections.

--- ConnectionManager Stats ---
Connections: 31
ConHistory: 110
ConStrCnt: 279
-------------------------------

To Reproduce Just run the DHT (or another Connection heavy service) and have the connection manager dump its stats every so often...

Expected behavior ConnectionStreamCount to only ever have as many entries as the current number of Connections (31 in this case)

Desktop (please complete the following information):

• Ubuntu / Linux

Is your feature request related to a problem? Please describe. Currently if we fail to dial a peer, either due to a connection timeout or a PeerID mismatch, we don't remove the peer from our peerstore.

Describe the solution you'd like We should remove this peer from the peerstore and issue an event / notification so services (such as the DHT) can be notified of the removal.

Describe alternatives you've considered We could perhaps just penalize the peer in question instead of immediately removing them. But that would require implementing a peer scoring system, which we should eventually do, but would take a little more effort.

Is your feature request related to a problem? Please describe. Nope

Describe the solution you'd like We should integrate swift-metrics into swift-libp2p so we can keep track of metrics and monitor performance!

Describe alternatives you've considered None

Additional context Things you can measure tend to get better! 🧐🔬

Is your feature request related to a problem? Please describe. Sort of... Libp2p should reuse connections to peers whenever possible. And swfit-libp2p does currently check for existing suitable connections before establishing a new one. But if we fire off two separate requests to the same peer immediately after one another, swift-libp2p will open two individual connections, due to the call to ConnectionManager.getConnectionsTo(:Multiaddr, ...) returning an empty array because we haven't had time to instantiate a connection.

Describe the solution you'd like The ConnectionManager should keep track of pending connections and bundle/queue multiple requests to the same remote peer while we're waiting for a single connection to establish. Once established, flush the pending requests through the connection.

Describe alternatives you've considered No other alternatives

Additional context None