feat(peer): ask a peer what it says about itself

The client answered a UserInfoRequest but could never send one, so a
user's profile — description, upload slots, queue length — was something
this client served and never saw. The reply (peer code 16) is now parsed
too, with the tolerances other clients carry: a picture is skipped rather
than kept, a length that overruns the message is clamped, and a message
that stops early (older clients, and Museek+ writing a boolean as an
integer) still yields every field before it.

soulseek-rs-lib/src/client/operations.rs

@@ -919,6 +919,11 @@ impl Client {
                             }
                         }
                     }
+                    ClientOperation::PeerInfoReceived { username, info } => {
+                        if let Ok(mut ctx) = client_context.write_safe() {
+                            ctx.store_peer_info(username, info);
+                        }
+                    }
                     ClientOperation::FolderContents {
                         username,
                         token,