Add the Edit Channel dialog

Recovers the official client's CreateChannelDialog layout so the widget
set, labels and tab order match: name/icon/password/topic/description
above Standard, Audio, Permissions and Advanced tabs.

Core gains ChannelSettings (diffed against the original so channeledit
only carries changed properties) and ChannelAdmin (channelinfo/edit,
channel permissions, the server icon store). TeamspeakConnection now
owns the event executor so it can drain queued notify events before
reading a command's result, which channelpermlist needs.

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

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

@@ -20,6 +20,10 @@ final class ChannelMenu {
         join.addActionListener(a -> actions.joinChannel(channel.id));
         menu.add(join);
         menu.addSeparator();
+        JMenuItem edit = new JMenuItem("Edit Channel", Icons.of("CHANNEL_EDIT"));
+        edit.addActionListener(a -> actions.editChannel(channel));
+        menu.add(edit);
+        menu.addSeparator();
         addSubscriptionItems(menu, channel, actions);
         JMenuItem files = new JMenuItem("Browse files", Icons.of("FILETRANSFER"));
         files.addActionListener(a -> actions.browseFiles(channel));