add notes about http-api ux

[daviddias]

No description provided.

[daviddias]

@whyrusleeping

[whyrusleeping]

👍 needs @jbenet's review though

[jbenet]

What does this look like in CLI UX? they need to match.

Some comments up-front:

• subscribe should not be able to be left open. it should always cancel without a socket ramining open, or continued requests from the user
• We can add route as a subcommand that tells the node to add a subscription and route the messages, but does not count as a "client's intent to subscribe", only that the node should behave as a router in the network. This state should be persistent and durable (i.e. changes config to disk, works across reboots)
• We are getting pubsub ls subcommand ipfs/kubo#3223 and pubsub peers subcommand ipfs/kubo#3224 -- does that satisfy some of these needs ?