feat: 添加 AI 服务，提供 AI 聊天、语音转文本和交易确认功能。

src/services/aiService.ts

@@ -108,7 +108,7 @@ export async function streamChatMessage(
   const token = localStorage.getItem('token'); // Assuming auth token is stored here
 
   // Use fetch directly for streaming support
-  const response = await fetch(`${import.meta.env.VITE_API_URL}/ai/chat/stream`, {
+  const response = await fetch(`${import.meta.env.VITE_API_BASE_URL}/ai/chat/stream`, {
     method: 'POST',
     headers: {
       'Content-Type': 'application/json',