fix: make canBeUsed non async

src/modules/tts-modes/none.ts

@@ -5,6 +5,9 @@ const ttsNone: TTSModule = {
 	getVoices: async (): Promise<Array<string>> => [],
 	generate: async (): Promise<TTSResponse> => {
 		return { data: Buffer.from([]) };
+	},
+	canBeUsed: (): boolean => {
+		return true;
 	}
 };