refactor: 提取公共工具函数到 shared/utils.js，消除 DRY 重复

- escapeHtml 8 处定义合并为 shared/utils.js 1 处：删除 shortcode.js、posts/show.html、settings/index.html、comments.js、energy.js、common.js 中的重复定义
- formatTime 6 处定义合并为 1 处：统一 ISO 时间格式化逻辑
- api() 5 处定义收敛：前台页面使用 shared/utils.js 统一 api(method,url,data)，admin 使用 common.js 的 api 对象
- showToast 3 处定义合并为 1 处：自包含内联样式，前后台通用
- admin/posts.js api 调用迁移为 api.post()

templates/MetaLab-2026/html/posts/show.html

@@ -376,17 +376,6 @@
     var currentFolderId = null;
     var loading = false;
 
-    function api(method, url, data) {
-        var opts = { method: method, headers: { 'Content-Type': 'application/json' } };
-        var token = getCSRFToken();
-        if (token) opts.headers['X-CSRF-Token'] = token;
-        if (data) opts.body = JSON.stringify(data);
-        return fetch(url, opts).then(function(r) {
-            if (r.status === 401) { window.location.href = '/auth/login?redirect=/posts/' + postId; throw new Error('unauthorized'); }
-            return r.json();
-        });
-    }
-
     // 更新按钮状态
     function updateBtn(favorited) {
         isFavorited = favorited;
@@ -624,28 +613,7 @@
     var currentPage = 1;
     var totalPages = 1;
 
-    // ====== 工具函数 ======
-    function api(method, url, data) {
-        var opts = { method: method, headers: { 'Content-Type': 'application/json' } };
-        var token = getCSRFToken();
-        if (token) opts.headers['X-CSRF-Token'] = token;
-        if (data) opts.body = JSON.stringify(data);
-        return fetch(url, opts).then(function(r) { return r.json(); });
-    }
-
-    function escapeHtml(text) {
-        var d = document.createElement('div');
-        d.textContent = text;
-        return d.innerHTML;
-    }
-
-    function formatTime(iso) {
-        var d = new Date(iso);
-        var pad = function(n) { return n < 10 ? '0'+n : n; };
-        return d.getFullYear() + '-' + pad(d.getMonth()+1) + '-' + pad(d.getDate()) + ' ' + pad(d.getHours()) + ':' + pad(d.getMinutes());
-    }
-
-    // ====== 渲染评论 HTML ======
+    // escapeHtml / formatTime / showToast / api 由 shared/utils.js 统一提供
     function buildCommentCard(c) {
         var time = c.created_at ? formatTime(c.created_at) : '';
         var author = c.author_name ? escapeHtml(c.author_name) : '用户已注销';
@@ -1057,19 +1025,8 @@
         });
     }
 
-    // ====== 评论高亮 + 已删除评论Toast ======
-    function showToast(msg) {
-        var toast = document.createElement('div');
-        toast.className = 'toast';
-        toast.textContent = msg;
-        toast.style.cssText = 'position:fixed;top:20px;left:50%;transform:translateX(-50%);background:rgba(0,0,0,0.85);color:#fff;padding:10px 24px;border-radius:6px;font-size:14px;z-index:9999;animation:fadeIn 0.3s ease';
-        document.body.appendChild(toast);
-        setTimeout(function() {
-            toast.style.opacity = '0';
-            toast.style.transition = 'opacity 0.3s';
-            setTimeout(function() { toast.remove(); }, 300);
-        }, 2500);
-    }
+    // ====== 评论高亮 ======
+    // showToast 由 shared/utils.js 统一提供
 
     function highlightComment(commentId) {
         var card = commentsList.querySelector('.comment-card[data-id="' + commentId + '"]') ||

templates/MetaLab-2026/html/settings/index.html

@@ -999,11 +999,11 @@
                     var sign = item.amount > 0 ? '+' : '';
                     html += '<div class="energy-log-item ' + cls + '">'
                         + '<div class="energy-log-meta">'
-                        + '<span class="energy-log-type">' + escapeHTML(item.type_name) + '</span>'
+                        + '<span class="energy-log-type">' + escapeHtml(item.type_name) + '</span>'
                         + '<span class="energy-log-time">' + formatTime(item.created_at) + '</span>'
                         + '</div>'
                         + '<div class="energy-log-info">'
-                        + '<span class="energy-log-desc">' + escapeHTML(item.description) + '</span>'
+                        + '<span class="energy-log-desc">' + escapeHtml(item.description) + '</span>'
                         + '<span class="energy-log-amount">' + sign + item.amount_display + ' 域能</span>'
                         + '</div>'
                         + '</div>';
@@ -1014,16 +1014,7 @@
                 logListEl.innerHTML = '<div class="energy-log-empty">加载失败</div>';
             });
 
-        function escapeHTML(str) {
-            var div = document.createElement('div');
-            div.appendChild(document.createTextNode(str));
-            return div.innerHTML;
-        }
-
-        function formatTime(isoStr) {
-            if (!isoStr) return '';
-            return isoStr.replace('T', ' ').replace(/\+.*/, '');
-        }
+        // escapeHtml / formatTime 由 shared/utils.js 统一提供
     })();
 
     // ===== 收藏夹 Tab =====
@@ -1032,26 +1023,14 @@
         var createBtn = document.getElementById('createFolderBtn');
         if (!listEl) return;
 
-        function esc(s) {
-            var d = document.createElement('div');
-            d.textContent = s || '';
-            return d.innerHTML;
-        }
-
-        function api(method, url, data) {
-            var opts = { method: method, headers: { 'Content-Type': 'application/json' } };
-            var token = getCSRFToken();
-            if (token) opts.headers['X-CSRF-Token'] = token;
-            if (data) opts.body = JSON.stringify(data);
-            return fetch(url, opts).then(function (r) { return r.json(); });
-        }
+        // escapeHtml / api 由 shared/utils.js 统一提供
 
         function loadFolders() {
             listEl.innerHTML = '<div class="energy-log-empty">加载中...</div>';
             api('GET', '/api/folders')
                 .then(function (d) {
                     if (!d.success) {
-                        listEl.innerHTML = '<div class="energy-log-empty">' + esc(d.message || '加载失败') + '</div>';
+                        listEl.innerHTML = '<div class="energy-log-empty">' + escapeHtml(d.message || '加载失败') + '</div>';
                         return;
                     }
                     if (!d.data || !d.data.folders || d.data.folders.length === 0) {
@@ -1064,7 +1043,7 @@
                         var pub = f.is_public ? '公开' : '私密';
                         html += '<div class="fav-folder-card">'
                             + '<div class="fav-folder-info">'
-                            + '<span class="fav-folder-name">' + esc(f.name) + isDefault + '</span>'
+                            + '<span class="fav-folder-name">' + escapeHtml(f.name) + isDefault + '</span>'
                             + '<span class="fav-folder-meta">' + (f.item_count || 0) + ' 篇文章 · ' + pub + '</span>'
                             + '</div>'
                             + '<div class="fav-folder-actions">'