Deduplicate stored protocols

[whyrusleeping]

We store every protocol that is supported by every peer we connect to. These protocols tend towards being long strings, and are common between pretty much every peer we connect to. Instead of storing these for each peer we connect to, we should probably map each string to an integer, and store those integers with each peer. This would reduce memory usage on my nodes by around 10% it looks like

[raulk]

Makes sense. Could you try switching to the datastore-backed peerstore in your setup? IPFS will soon have an experimental flag (ipfs/kubo#6080), and medium-term I’d like to make this implementation the default.