refactor: migrate state imports from contexts to stores directory

src/utils/storage.ts

@@ -11,15 +11,27 @@
  */
 import { createStorage, type Storage } from "unstorage";
 import localStorageDriver from "unstorage/drivers/localstorage";
+import memoryDriver from "unstorage/drivers/memory";
 import type { ZodType } from "zod";
 
 import { Result, type Result as ResultT } from "@/utils/result";
 
 export class SpAsyncUtil {
   // ===== 私有静态状态 =====
-  private static _storage: Storage = createStorage({
-    driver: localStorageDriver({ base: "cozsweet:" }),
-  });
+  // 环境判断 + lazy 初始化：SSR 用 memory driver，浏览器用 localStorage driver。
+  // unstorage 1.10+ 要求显式传入 localStorage，故这里同步注入 window.localStorage。
+  private static _storage: Storage = (() => {
+    if (typeof window === "undefined") {
+      // SSR 环境：无 window，降级为内存驱动
+      return createStorage({ driver: memoryDriver() });
+    }
+    // 浏览器环境：使用 localStorage 驱动
+    return createStorage({
+      driver: localStorageDriver({
+        base: "cozsweet:",
+      }),
+    });
+  })();
 
   // 私有构造函数：禁止实例化（对齐 Dart `SpAsyncUtil._()`）
   private constructor() {}