test(grok): 补齐音频与搜索计价接口契约

backend/internal/server/api_contract_test.go

@@ -371,6 +371,10 @@ func TestAPIContracts(t *testing.T) {
 						"video_price_720p": null,
 						"video_price_1080p": null,
 						"web_search_price_per_call": null,
+						"search_price_per_1k": null,
+						"audio_tts_price_per_million_chars": null,
+						"audio_stt_price_per_hour": null,
+						"audio_realtime_price_per_min": null,
 						"allow_image_generation": false,
 						"allow_batch_image_generation": false,
 						"batch_image_discount_multiplier": 0,