feat: 小程序演示版改造 + 服务端安全加固

- 许愿树移除付费许愿/商品选择/微信支付调用，全部走免费许愿
- 许愿发布前接入微信 msgSecCheck v2 内容安全检测（access_token 内存缓存）
- 许愿字数限制改为按字符计算（中文按 1 字计）
- 占卜页改名「民俗趣算」并弱化「算命」措辞，占卜/每日运势页加文化声明
- 生产环境 JWT_SECRET 缺失或为默认值/不足 32 位时拒绝启动

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

mini/pages/wish-tree/wish-tree.js

@@ -54,11 +54,7 @@ Page({
     fireflies: [],
     showCreateModal: false,
     wishContent: '',
-    wishType: 'free',
     maxFreeLength: 20,
-    maxPaidLength: 100,
-    products: [],
-    selectedProduct: null,
   },
 
   onLoad() {
@@ -72,7 +68,6 @@ Page({
 
     this.initAmbiance();
     this.loadTrees();
-    this.loadProducts();
   },
 
   onUnload() {
@@ -407,7 +402,7 @@ Page({
         id: i + 1,
         content: texts[i % texts.length],
         author: authors[i % authors.length],
-        type: i % 5 === 0 ? 'paid' : 'free',
+        type: 'free',
         position: i === 0 ? 100 : 0,
         isTop: i === 0,
         createdAt: new Date(Date.now() - i * 3600 * 1000).toISOString(),
@@ -427,26 +422,6 @@ Page({
     this.setData({ detailWish: null });
   },
 
-  // 加载许愿商品
-  async loadProducts() {
-    try {
-      const res = await request({ url: '/api/wish/products', method: 'GET' });
-      if (res.code === 0) {
-        this.setData({ products: res.data.list || [] });
-        return;
-      }
-    } catch (err) {
-      console.error('加载商品失败:', err);
-    }
-    this.setData({
-      products: [
-        { id: 1, name: '普通许愿条', price: 100, duration: 7 },
-        { id: 2, name: '精品许愿条', price: 500, duration: 30 },
-        { id: 3, name: '至尊许愿条', price: 2000, duration: 90 },
-      ],
-    });
-  },
-
   // 打开/关闭许愿弹窗
   openCreateModal() {
     this.setData({ showCreateModal: true });
@@ -456,8 +431,6 @@ Page({
     this.setData({
       showCreateModal: false,
       wishContent: '',
-      wishType: 'free',
-      selectedProduct: null,
     });
   },
 
@@ -465,16 +438,6 @@ Page({
     this.setData({ wishContent: e.detail.value });
   },
 
-  selectType(e) {
-    this.setData({ wishType: e.currentTarget.dataset.type });
-  },
-
-  selectProduct(e) {
-    const id = e.currentTarget.dataset.id;
-    const product = this.data.products.find((p) => p.id === id);
-    this.setData({ selectedProduct: product });
-  },
-
   // 当前树ID
   currentTreeId() {
     const { trees, currentTreeIndex } = this.data;
@@ -484,54 +447,32 @@ Page({
 
   // 提交许愿
   async submitWish() {
-    const { wishContent, wishType, selectedProduct, maxFreeLength, maxPaidLength } = this.data;
+    const { wishContent, maxFreeLength } = this.data;
 
     if (!wishContent.trim()) {
       wx.showToast({ title: '请输入许愿内容', icon: 'none' });
       return;
     }
 
-    const maxLength = wishType === 'free' ? maxFreeLength : maxPaidLength;
-    if (wishContent.length > maxLength) {
-      wx.showToast({ title: `最多输入${maxLength}个字`, icon: 'none' });
-      return;
-    }
-
-    if (wishType === 'paid' && !selectedProduct) {
-      wx.showToast({ title: '请选择许愿商品', icon: 'none' });
+    if (wishContent.length > maxFreeLength) {
+      wx.showToast({ title: `最多输入${maxFreeLength}个字`, icon: 'none' });
       return;
     }
 
     try {
-      if (wishType === 'paid') {
-        const orderRes = await request({
-          url: '/api/pay/create',
-          method: 'POST',
-          data: {
-            type: 'wish',
-            productId: selectedProduct.id,
-            content: wishContent,
-            treeId: this.currentTreeId(),
-          },
-        });
-        if (orderRes.code === 0) {
-          await this.wxPay(orderRes.data);
-        }
-      } else {
-        const res = await request({
-          url: '/api/wish/create',
-          method: 'POST',
-          data: {
-            content: wishContent,
-            type: 'free',
-            treeId: this.currentTreeId(),
-          },
-        });
-        if (res.code === 0) {
-          wx.showToast({ title: '许愿成功', icon: 'success' });
-          this.closeCreateModal();
-          this.loadTreeWishes(this.data.currentTreeIndex, true);
-        }
+      const res = await request({
+        url: '/api/wish/create',
+        method: 'POST',
+        data: {
+          content: wishContent,
+          type: 'free',
+          treeId: this.currentTreeId(),
+        },
+      });
+      if (res.code === 0) {
+        wx.showToast({ title: '许愿成功', icon: 'success' });
+        this.closeCreateModal();
+        this.loadTreeWishes(this.data.currentTreeIndex, true);
       }
     } catch (err) {
       console.error('许愿失败:', err);
@@ -539,30 +480,6 @@ Page({
     }
   },
 
-  // 微信支付
-  async wxPay(orderData) {
-    return new Promise((resolve, reject) => {
-      wx.requestPayment({
-        timeStamp: orderData.timeStamp,
-        nonceStr: orderData.nonceStr,
-        package: orderData.package,
-        signType: orderData.signType,
-        paySign: orderData.paySign,
-        success: () => {
-          wx.showToast({ title: '支付成功', icon: 'success' });
-          this.closeCreateModal();
-          this.loadTreeWishes(this.data.currentTreeIndex, true);
-          resolve();
-        },
-        fail: (err) => {
-          console.error('支付失败:', err);
-          wx.showToast({ title: '支付失败', icon: 'none' });
-          reject(err);
-        },
-      });
-    });
-  },
-
   // 分享
   onShareAppMessage() {
     return {