Auto-join when adding new network on irc:// link click

Closes: https://todo.sr.ht/~emersion/gamja/111

lib/client.js

@@ -861,4 +861,16 @@ export default class Client extends EventTarget {
 
 		this.send({ command: "MONITOR", params: ["-", target] });
 	}
+
+	createBouncerNetwork(attrs) {
+		let msg = {
+			command: "BOUNCER",
+			params: ["ADDNETWORK", irc.formatTags(attrs)],
+		};
+		return this.roundtrip(msg, (msg) => {
+			if (msg.command === "BOUNCER" && msg.params[0] === "ADDNETWORK") {
+				return msg.params[1];
+			}
+		});
+	}
 }