Add it to the websocket handshake.

client: Here's a giftwrapped event

relay: I don't know you but for 1ksat we're cool

client: here, have some nuts worth 1ksat ( nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg that should work, right? )