fix(xai/minor): update Grok realtime voices to match xAI API (#1240)

Author: Hormold

.changeset/xai-update-grok-voices.md

@@ -0,0 +1,5 @@
+---
+'@livekit/agents-plugin-xai': patch
+---
+
+update Grok realtime voices to match xAI API (eve, ara, rex, sal, leo); default voice is now lowercase `ara`

plugins/xai/src/realtime/realtime_model.ts

@@ -8,7 +8,7 @@ type OpenAIRealtimeModelOptions = ConstructorParameters<typeof OpenAIRealtimeMod
 
 const XAI_BASE_URL = 'wss://api.x.ai/v1';
 const DEFAULT_MODEL = 'grok-4-1-fast-non-reasoning';
-const DEFAULT_VOICE = 'Ara';
+const DEFAULT_VOICE = 'ara';
 
 const XAI_DEFAULT_TURN_DETECTION = {
   type: 'server_vad' as const,
@@ -19,7 +19,7 @@ const XAI_DEFAULT_TURN_DETECTION = {
   interrupt_response: true,
 };
 
-export type GrokVoices = 'Ara' | 'Cora' | 'Sage';
+export type GrokVoices = 'eve' | 'ara' | 'rex' | 'sal' | 'leo';
 
 export interface RealtimeModelOptions extends Omit<OpenAIRealtimeModelOptions, 'model'> {
   model?: string;