feat: 更新 API 前缀配置，调整 Vite 代理设置以匹配新环境

frontend/src/app/services/api.ts

@@ -2,7 +2,8 @@ const TOKEN_KEY = "auth_token";
 
 const env = (import.meta as any).env || {};
 const API_PREFIX: string = (env.VITE_API_PREFIX as string) || "/api";
-const APP_BASE_URL: string = (env.BASE_URL as string) || "/";
+// APP_BASE_URL = basename = 从 API_PREFIX 提取（"/app_03/api" → "/app_03"）
+const APP_BASE_URL: string = API_PREFIX.replace(/\/api\/?$/, '') || '/';
 
 function joinPrefix(prefix: string, path: string) {
   const p = prefix.endsWith("/") ? prefix.slice(0, -1) : prefix;