feat: 新增支付页面接口，为接入支付宝做准备

- GET /payment: 套餐选择页（无需认证，外部浏览器打开）
- GET /payment/page: 支付引导页（需 JWT，创建订单）
- GET /payment/pay: 支付宝电脑网站支付占位页（需 JWT）
- AppState 新增支付宝配置字段（可选）
- afterbody.js: PDF下载增加状态提示和重试按钮

static/js/afterbody.js

@@ -232,17 +232,95 @@ const WeatherReport = (function () {
         html2pdf().set(options).from(htmlContent).save();
     }
 
+    // 下载状态管理（供重试使用）
+    let downloadState = {
+        ready: false,
+        html: null,
+        filename: null,
+    };
+
+    // 下载提示浮层
+    function showDownloadPrompt(type, message) {
+        let overlay = document.getElementById("download-overlay");
+        if (!overlay) {
+            overlay = document.createElement("div");
+            overlay.id = "download-overlay";
+            overlay.innerHTML = `
+                <style>
+                    #download-overlay {
+                        position: fixed;
+                        top: 0; left: 0; right: 0;
+                        z-index: 9999;
+                        padding: 16px;
+                        text-align: center;
+                        font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
+                        transition: opacity 0.3s;
+                        pointer-events: none;
+                    }
+                    #download-overlay .msg {
+                        display: inline-block;
+                        background: rgba(0,0,0,0.75);
+                        color: #fff;
+                        padding: 12px 24px;
+                        border-radius: 8px;
+                        font-size: 14px;
+                    }
+                    #download-overlay .retry-btn {
+                        display: inline-block;
+                        margin-left: 12px;
+                        background: #1677ff;
+                        color: #fff;
+                        border: none;
+                        padding: 8px 16px;
+                        border-radius: 6px;
+                        font-size: 13px;
+                        cursor: pointer;
+                        pointer-events: auto;
+                    }
+                </style>
+                <span class="msg" id="dl-msg"></span>
+                <span class="retry-btn" id="dl-retry" style="display:none" onclick="WeatherReport.retryDownload()">重新下载</span>
+            `;
+            document.body.appendChild(overlay);
+        }
+        const msgEl = document.getElementById("dl-msg");
+        const retryEl = document.getElementById("dl-retry");
+        if (msgEl) msgEl.textContent = message;
+        if (retryEl) {
+            if (type === "loading" || type === "success") {
+                retryEl.style.display = "none";
+            } else {
+                retryEl.style.display = "inline-block";
+            }
+        }
+    }
+
+    function hideDownloadPrompt() {
+        const overlay = document.getElementById("download-overlay");
+        if (overlay) {
+            overlay.style.opacity = "0";
+            setTimeout(() => { if (overlay) overlay.remove(); }, 300);
+        }
+    }
+
+    function retryDownload() {
+        if (!downloadState.ready || !downloadState.html || !downloadState.filename) {
+            showDownloadPrompt("error", "数据未准备好，请刷新页面重试");
+            return;
+        }
+        downloadPDF(downloadState.html, downloadState.filename);
+        showDownloadPrompt("success", "正在重新下载，请稍候...");
+    }
+
     function init() {
         if (typeof window.weatherData === "undefined") {
             console.error("错误：window.weatherData 未定义");
+            showDownloadPrompt("error", "数据加载失败，请刷新页面重试");
             return;
         }
 
         const data = window.weatherData;
         console.log("【调试】从后端获取的 weatherData:", data);
-        console.log("【调试】inspectionType:", data.inspectionType);
-        console.log("【调试】assignmentNumber:", data.assignmentNumber);
-        console.log("【调试】title:", data.title);
 
         const versionEl = document.querySelector(".version");
         if (versionEl) {
@@ -251,7 +329,30 @@ const WeatherReport = (function () {
 
         const html = buildReportHTML(data);
         const filename = `${data.id}-${data.version || "unknown"}.pdf`;
-        downloadPDF(html, filename);
+
+        // 保存下载状态，供重试使用
+        downloadState.ready = true;
+        downloadState.html = html;
+        downloadState.filename = filename;
+
+        // 显示下载中提示
+        showDownloadPrompt("loading", "正在生成 PDF，请稍候...");
+
+        // 延迟执行下载，让用户看到提示
+        setTimeout(() => {
+            downloadPDF(html, filename);
+            // 显示成功提示，3秒后消失
+            showDownloadPrompt("success", "PDF 开始下载...");
+            setTimeout(() => hideDownloadPrompt(), 3000);
+            // 额外等3秒，如果提示已消失（下载成功）则不再显示重试
+            // 如果提示还在（下载失败），则替换为重试按钮
+            setTimeout(() => {
+                const overlay = document.getElementById("download-overlay");
+                if (overlay) {
+                    showDownloadPrompt("retry", "下载未开始，请点击重试");
+                }
+            }, 3300);
+        }, 300);
     }
 
     document.addEventListener("DOMContentLoaded", function () {
@@ -293,5 +394,6 @@ const WeatherReport = (function () {
         init,
         toggleFormula,
         showNotification,
+        retryDownload,
     };
 })();