Remove agent string

The agent string was inspired by the HTTP User-Agent header to serve as
a way to identify what's connecting to the cluster.  While there may
have been vision of other software connecting to a controller than the
Clusterio provided ones this seems highly unlikely to ever happen.

Remove redundant agent string for now.

packages/controller/src/WsServer.ts

@@ -261,9 +261,9 @@ ${err.stack}`
 		}
 
 		logger.info(
-			`WsServer | registered host ${data.name} (${data.id}) using agent ${data.agent} ${data.version}`
+			`WsServer | registered host ${data.name} (${data.id}) using version ${data.version}`
 		);
-		if (data.agent === "Clusterio Host" && data.version !== packageVersion) {
+		if (data.version !== packageVersion) {
 			logger.warn(
 				`Host ${data.name} (${data.id}) connected using version ${data.version} which does not match the ` +
 				`version of the controller is currently running (${packageVersion}). It may not work as expected.`