Connect a left-clicked bookmark on the current tab

Middle-click still opens the server in a new tab.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

ts3-client/swing/src/main/java/com/ts3client/ui/ServerTab.java

@@ -230,6 +230,24 @@ final class ServerTab implements ServerTabConnectionEvents.Listener {
         }, "identity-resolve").start();
     }
 
+    /**
+     * Replaces this tab's connection: leaves the server it is on, then connects to the
+     * new one in its place — what left-clicking a bookmark does.
+     */
+    void switchTo(String address, int port, String nickname, String password, String identityId,
+                  String channel, String channelPassword) {
+        if (!isBusy()) {
+            connect(address, port, nickname, password, identityId, channel, channelPassword);
+            return;
+        }
+        new Thread(() -> {
+            conn.disconnectBlocking("Switching servers");
+            // Queued behind the disconnect's own UI work, which clears the "connecting" flag.
+            SwingUtilities.invokeLater(() ->
+                    connect(address, port, nickname, password, identityId, channel, channelPassword));
+        }, "ts3j-switch-server").start();
+    }
+
     void disconnect() {
         if (conn.isConnected()) conn.disconnect();
     }