* feat: add uPnP nat manager
Adds a really basic nat manager that attempts to use UPnP to punch
a hole through your router for any IPV4 tcp addresses you have
configured.
Adds any configured addresses to the node's observed addresses list
and adds observed addresses to `libp2p.multiaddrs` so we exchange
them with peers when performing `identify` and people can dial you.
Adds configuration options under `config.nat`
Hole punching is async to not affect start up time.
Co-authored-by: Vasco Santos <vasco.santos@moxy.studio>
