fix(chat): prevent guest quota reset on read failures

src/utils/storage.ts

@@ -19,20 +19,9 @@ import { Result, type Result as ResultT } from "@/utils/result";
 
 export class SpAsyncUtil {
   // ===== 私有静态状态 =====
-  // 环境判断 + lazy 初始化：SSR 用 memory driver，浏览器用 localStorage driver。
+  // 环境判断 + 安全初始化：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:",
-      }),
-    });
-  })();
+  private static _storage: Storage = createDefaultStorage();
 
   // 私有构造函数：禁止实例化（对齐 Dart `SpAsyncUtil._()`）
   private constructor() {}
@@ -170,11 +159,11 @@ export class SpAsyncUtil {
     key: string,
     schema: ZodType<T>,
   ): Promise<ResultT<T | null>> {
-    const r = await SpAsyncUtil.getString(key);
-    if (!r.success) return Result.err(r.error);
-    if (r.data === null) return Result.ok(null);
     try {
-      const parsed = schema.parse(JSON.parse(r.data));
+      const value = await SpAsyncUtil._storage.getItem<unknown>(key);
+      if (value === null || value === undefined) return Result.ok(null);
+      const json = typeof value === "string" ? JSON.parse(value) : value;
+      const parsed = schema.parse(json);
       return Result.ok(parsed);
     } catch (e) {
       return Result.err(toError(e));
@@ -230,3 +219,21 @@ export class SpAsyncUtil {
 function toError(e: unknown): Error {
   return e instanceof Error ? e : new Error(String(e));
 }
+
+function createDefaultStorage(): Storage {
+  if (typeof window === "undefined") {
+    return createStorage({ driver: memoryDriver() });
+  }
+
+  try {
+    return createStorage({
+      driver: localStorageDriver({
+        base: "cozsweet:",
+        localStorage: window.localStorage,
+        window,
+      }),
+    });
+  } catch {
+    return createStorage({ driver: memoryDriver() });
+  }
+}