fix(openai): 修复 service_tier 类型断言问题

groq 有不同的 service tier 配置，不符合 openai 接口类型，因此需要显式类型断言

src/renderer/src/aiCore/clients/openai/OpenAIResponseAPIClient.ts

@@ -15,6 +15,7 @@ import {
   MCPTool,
   MCPToolResponse,
   Model,
+  OpenAIServiceTier,
   Provider,
   ToolCallResponse,
   WebSearchSource
@@ -448,7 +449,8 @@ export class OpenAIResponseAPIClient extends OpenAIBaseClient<
           max_output_tokens: maxTokens,
           stream: streamOutput,
           tools: !isEmpty(tools) ? tools : undefined,
-          service_tier: this.getServiceTier(model),
+          // groq 有不同的 service tier 配置，不符合 openai 接口类型
+          service_tier: this.getServiceTier(model) as OpenAIServiceTier,
           ...(this.getReasoningEffort(assistant, model) as OpenAI.Reasoning),
           // 只在对话场景下应用自定义参数，避免影响翻译、总结等其他业务逻辑
           ...(coreRequest.callType === 'chat' ? this.getCustomParameters(assistant) : {})