feat: log in with soulseek-rs's own client major version (176) (#13)

The Login message hardcoded SoulseekQt's major version 157, so the
server could not tell soulseek-rs apart from the official client. The
protocol document now reserves a unique major version per project, so
claim 176 and send it via a new ClientVersion on ClientSettings.

Clients and bots built on the library keep major 176 and pick their own
minor version (default 1); the reference CLI/TUI logs in with minor 100.

Refs #12

soulseek-rs/tests/cli_e2e.rs

@@ -442,6 +442,7 @@ impl TestServer {
             enable_listen: true,
             listen_port: port,
             shared_directories: shares,
+            version: soulseek_rs::ClientVersion::default(),
         });
         client.connect().expect("peer connect");
         assert!(client.login().expect("peer login"), "peer should log in");