feat: automatically acquire WSS certificates from libp2p.direct

[aschmahmann]

This PR is WIP but the intention is to allow any publicly reachable node on the network to be reachable via Secure WebSockets and thereby improve reachability from browsers. For anyone who reads this and is unfamiliar with this work, don't worry plenty of documentation to come before we're ready to merge.

TLDR

$ ipfs config --json Swarm.ForgeClient.Enabled true
$ export FORGE_ACCESS_TOKEN="secret" # optional secret, necessary when testing for now 
$ # (TODO) ipfs config --json Swarm.ForgeClient.ForgeAuth "secret" 

TODO

Some outstanding items here are:

• the libp2p.direct service needs to be ready for production use
• libp2phttp: HTTP Peer ID Authentication libp2p/go-libp2p#2854 lands
• documentation
• need to be happy with the config file syntax
• remove debugging logs associated with acquiring certificates
• we should probably wait until we have confidence in our external addresses before trying to get a certificate
• multiplex WSS on the same port as TCP (e.g. by muxing on the ALPN in the TLS cert) so people don't need to open new ports
• there's currently an issue where the application doesn't realize it's acquired a certificate and that it's ready for use (happens at least on first acquisition)
• figure out what's going on with excessive logs like "http: TLS handshake error from ip:port: EOF"

[lidel]

TODO: remove once libp2p/go-libp2p#2854 lands

[lidel]

TODO: too low level, we need to move this to p2p-forge/client library, and call specific funcs here:

• WithForgeAuth(authKey)
• WithUserAgent(GetUserAgentVersion())