refactor(subscription): Phase 2 - 迁移到 Redux 状态管理

重构目标: 使用 Redux 管理订阅数据,替代本地状态

Phase 2 完成:
✅ 创建 subscriptionSlice.js (143行)
  - Redux Toolkit createSlice + createAsyncThunk
  - 管理订阅信息、loading、error、Modal 状态
  - fetchSubscriptionInfo 异步 thunk
  - resetToFree reducer (登出时调用)

✅ 注册到 Redux Store
  - 添加 subscriptionReducer 到 store

✅ 重构 useSubscription Hook (182行)
  - 从本地状态迁移到 Redux (useSelector + useDispatch)
  - 保留所有权限检查逻辑
  - 新增: isSubscriptionModalOpen, open/closeSubscriptionModal
  - 自动加载订阅数据 (登录时)

✅ 重构 HomeNavbar 使用 Redux
  - 替换 useSubscriptionData → useSubscription
  - 删除 ./hooks/useSubscriptionData.js

架构优势:
✅ 全局状态共享 - 多组件可访问订阅数据
✅ Redux DevTools 可调试
✅ 异步逻辑统一管理 (createAsyncThunk)
✅ 与现有架构一致 (authModalSlice 等)

性能优化:
✅ Redux 状态优化,减少不必要渲染
✅ useSelector 精确订阅,只在相关数据变化时更新

累计优化:
- 原始: 1623行
- Phase 1后: 1573行 (↓ 50行)
- Phase 2后: 1533行 (↓ 90行, -5.5%)
- 新增 Redux 逻辑: subscriptionSlice (143行) + Hook (182行)

下一步: Phase 3+ 继续拆分组件

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/store/slices/subscriptionSlice.js

@@ -0,0 +1,143 @@
+// src/store/slices/subscriptionSlice.js
+// 订阅信息状态管理 Redux Slice
+
+import { createSlice, createAsyncThunk } from '@reduxjs/toolkit';
+import { logger } from '../../utils/logger';
+import { getApiBase } from '../../utils/apiConfig';
+
+/**
+ * 异步 Thunk: 获取用户订阅信息
+ */
+export const fetchSubscriptionInfo = createAsyncThunk(
+    'subscription/fetchInfo',
+    async (_, { rejectWithValue }) => {
+        try {
+            const base = getApiBase();
+            logger.debug('subscriptionSlice', '开始加载订阅信息');
+
+            const response = await fetch(base + '/api/subscription/current', {
+                credentials: 'include',
+            });
+
+            if (!response.ok) {
+                throw new Error(`HTTP ${response.status}`);
+            }
+
+            const data = await response.json();
+
+            if (data.success && data.data) {
+                // 数据标准化处理
+                const normalizedData = {
+                    type: (data.data.type || data.data.subscription_type || 'free').toLowerCase(),
+                    status: data.data.status || 'active',
+                    days_left: data.data.days_left || 0,
+                    is_active: data.data.is_active !== false,
+                    end_date: data.data.end_date || null
+                };
+
+                logger.info('subscriptionSlice', '订阅信息加载成功', normalizedData);
+                return normalizedData;
+            } else {
+                // API 返回成功但无数据，返回默认免费版
+                return {
+                    type: 'free',
+                    status: 'active',
+                    days_left: 0,
+                    is_active: false,
+                    end_date: null
+                };
+            }
+        } catch (error) {
+            logger.error('subscriptionSlice', '加载订阅信息失败', error);
+            return rejectWithValue(error.message);
+        }
+    }
+);
+
+/**
+ * Subscription Slice
+ * 管理用户订阅信息和订阅 Modal 状态
+ */
+const subscriptionSlice = createSlice({
+    name: 'subscription',
+    initialState: {
+        // 订阅信息
+        info: {
+            type: 'free',
+            status: 'active',
+            days_left: 0,
+            is_active: false,
+            end_date: null
+        },
+        // 加载状态
+        loading: false,
+        error: null,
+        // 订阅 Modal 状态
+        isModalOpen: false,
+    },
+    reducers: {
+        /**
+         * 打开订阅 Modal
+         */
+        openModal: (state) => {
+            state.isModalOpen = true;
+            logger.debug('subscriptionSlice', '打开订阅 Modal');
+        },
+
+        /**
+         * 关闭订阅 Modal
+         */
+        closeModal: (state) => {
+            state.isModalOpen = false;
+            logger.debug('subscriptionSlice', '关闭订阅 Modal');
+        },
+
+        /**
+         * 重置为免费版 (用户登出时调用)
+         */
+        resetToFree: (state) => {
+            state.info = {
+                type: 'free',
+                status: 'active',
+                days_left: 0,
+                is_active: false,
+                end_date: null
+            };
+            state.loading = false;
+            state.error = null;
+            logger.debug('subscriptionSlice', '重置订阅信息为免费版');
+        },
+    },
+    extraReducers: (builder) => {
+        builder
+            // fetchSubscriptionInfo - pending
+            .addCase(fetchSubscriptionInfo.pending, (state) => {
+                state.loading = true;
+                state.error = null;
+            })
+            // fetchSubscriptionInfo - fulfilled
+            .addCase(fetchSubscriptionInfo.fulfilled, (state, action) => {
+                state.loading = false;
+                state.info = action.payload;
+                state.error = null;
+            })
+            // fetchSubscriptionInfo - rejected
+            .addCase(fetchSubscriptionInfo.rejected, (state, action) => {
+                state.loading = false;
+                state.error = action.payload || 'Unknown error';
+                // 加载失败时保持当前状态，不重置为免费版
+            });
+    },
+});
+
+// 导出 actions
+export const { openModal, closeModal, resetToFree } = subscriptionSlice.actions;
+
+// 导出 selectors
+export const selectSubscriptionInfo = (state) => state.subscription.info;
+export const selectSubscriptionLoading = (state) => state.subscription.loading;
+export const selectSubscriptionError = (state) => state.subscription.error;
+export const selectSubscriptionModalOpen = (state) => state.subscription.isModalOpen;
+
+// 导出 reducer
+export default subscriptionSlice.reducer;