Add default channel to bookmarks

Bookmarks can store a channel to join on connect, given either as a
"/"-separated path or a channel id, plus an optional channel password.
"Add bookmark" offers to remember the channel you are currently in.

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

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

@@ -124,6 +124,10 @@ public final class BookmarksDialog extends JDialog {
         JTextField port = new JTextField(Integer.toString(b.port));
         JTextField nick = new JTextField(b.nickname == null ? "" : b.nickname);
         JPasswordField password = new JPasswordField(b.password == null ? "" : b.password);
+        JTextField channel = new JTextField(b.channel == null ? "" : b.channel);
+        channel.setToolTipText("Channel path, e.g. \"Lobby/Games\", or a channel id. "
+                + "Leave empty for the server's default channel.");
+        JPasswordField channelPassword = new JPasswordField(b.channelPassword == null ? "" : b.channelPassword);
         IdentityChooser identity = new IdentityChooser(identities, true, b.identityId);
 
         JPanel form = new JPanel(new GridLayout(0, 1, 0, 2));
@@ -137,6 +141,10 @@ public final class BookmarksDialog extends JDialog {
         form.add(nick);
         form.add(new JLabel("Password (optional):"));
         form.add(password);
+        form.add(new JLabel("Default channel (path or id, optional):"));
+        form.add(channel);
+        form.add(new JLabel("Channel password (optional):"));
+        form.add(channelPassword);
         form.add(new JLabel("Identity:"));
         form.add(identity);
 
@@ -157,6 +165,8 @@ public final class BookmarksDialog extends JDialog {
         }
         b.nickname = nick.getText().trim();
         b.password = new String(password.getPassword());
+        b.channel = channel.getText().trim();
+        b.channelPassword = new String(channelPassword.getPassword());
         b.identityId = identity.getSelectedIdentityId();
         return true;
     }