Lay out the Options dialog like TeamSpeak 3's

A sidebar of pages with large icons replaces the tabs, and each page
opens under a banner with its title, subtitle and icon. OK, Cancel and
Apply sit below, and the dialog reopens on the last page used.

The pages follow TS3's: Application (muted-microphone warning, reported
client version), myTeamSpeak, Playback, Capture, Design, Hotkeys,
Contacts, Chat and Notifications. Capture now holds everything from the
microphone to the server: the device and gain, activation with the
microphone test, signal processing and the encoder, laid out in one
grid so its columns line up. Forms are grouped under section headings.

Cancel now goes back to what was last applied, and closing the window
cancels too, so a theme or icon pack being tried out is put back.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ts3-client/README.md

@@ -292,7 +292,7 @@ swing/  com.ts3client
     ├── Spacers              TS3 spacer-channel name parsing/rendering
     ├── InfoPanel            channel description / client group + details view
     ├── ChatPanel            chat log + input
-    ├── SettingsDialog       the Options dialog; one panel per tab (DevicesPanel, …, ChatLogsPanel)
+    ├── SettingsDialog       the Options dialog: TS3-style page sidebar + banner; one panel per page (ApplicationPanel, …, ChatLogsPanel)
     ├── HotkeysPanel         hotkey list (Options → Hotkeys)
     ├── HotkeyDialog         add/edit one hotkey: action, combination, trigger, scope
     ├── HotkeyService        bindings + engine + input hook, for the dialogs