/**
 * TTS Commands
 *
 * Built-in commands for TTS management:
 * - /tts - Show TTS status
 * - /tts on - Enable TTS
 * - /tts off - Disable TTS
 * - /tts always - Set trigger mode to always
 * - /tts inbound - Set trigger mode to inbound
 * - /tts tagged - Set trigger mode to tagged
 * - /tts never - Set trigger mode to off
 * - /tts provider <provider> - Set TTS provider
 * - /tts voice <voice> - Set TTS voice
 */
export declare function registerTTSCommands(): void;