fix: 修复 wangEditor 布局、预览、图片上传和链接样式

- 修复编辑区高度未撑满问题
- 预览改用 getHtml() 直接展示
- 图片上传改用 fetch + credentials:same-origin（修复 CSRF 403）
- 添加帖子正文链接蓝色+下划线样式
- 草稿改用 getHtml() 保存，恢复时正确还原格式
- 草稿改为每 300 字 + 停笔 10 秒双重触发
- 空编辑区不保存草稿
- 代码块语言标签通过 DOMParser 注入（编辑器 + 预览）

templates/MetaLab-2026/static/css/posts.css

@@ -104,15 +104,63 @@
     margin-bottom: 12px;
 }
 
+.post-detail-body a {
+    color: var(--color-accent);
+    text-decoration: underline;
+    text-underline-offset: 2px;
+    transition: color 0.2s;
+}
+
+.post-detail-body a:hover {
+    color: #2980b9;
+}
+
 .post-detail-body pre {
+    position: relative;
     background: #f3f4f6;
     padding: 16px;
+    padding-top: 36px;
     border-radius: 8px;
     overflow-x: auto;
     font-size: 14px;
     line-height: 1.5;
 }
 
+/* 代码块语言标签（编辑器内 + 预览页通用） */
+.post-detail-body pre,
+#editor-container [data-slate-editor] pre {
+    position: relative;
+    background: #f3f4f6;
+    padding: 16px;
+    padding-top: 36px;
+    border-radius: 8px;
+    overflow-x: auto;
+    font-size: 14px;
+    line-height: 1.5;
+}
+
+/* 通过 JS 动态注入语言标签，因为 CSS attr() 无法从 class 中提取 */
+.code-lang-label {
+    position: absolute;
+    top: 0;
+    left: 0;
+    right: 0;
+    padding: 4px 16px;
+    background: #e5e7eb;
+    color: #6b7280;
+    font-size: 11px;
+    font-weight: 600;
+    border-radius: 8px 8px 0 0;
+    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
+}
+
+.post-detail-body pre code,
+#editor-container [data-slate-editor] pre code {
+    background: transparent !important;
+    padding: 0 !important;
+    font-size: inherit !important;
+}
+
 .post-detail-body code {
     background: #f3f4f6;
     padding: 2px 6px;
@@ -223,6 +271,12 @@
 /* 编辑器整体容器 */
 #editor-container {
     background: #fff;
+    height: 100%;
+}
+
+/* wangEditor 内部文本容器撑满 */
+#editor-container .w-e-text-container {
+    height: 100% !important;
 }
 
 /* 编辑区域 */
@@ -379,6 +433,42 @@
     font-style: normal !important;
 }
 
+/* 编辑器内代码块样式 */
+#editor-container [data-slate-editor] pre {
+    position: relative;
+    background: #f3f4f6 !important;
+    padding: 12px 16px !important;
+    padding-top: 32px !important;
+    border-radius: 8px !important;
+    font-family: 'Menlo', 'Consolas', 'Monaco', 'Liberation Mono', monospace !important;
+    font-size: 13px !important;
+    line-height: 1.6 !important;
+    overflow-x: auto !important;
+    margin: 12px 0 !important;
+}
+
+/* 编辑器内代码块语言标签 */
+#editor-container [data-slate-editor] pre::before {
+    content: attr(data-language);
+    position: absolute;
+    top: 0;
+    left: 0;
+    right: 0;
+    padding: 3px 16px;
+    background: #e5e7eb;
+    color: #6b7280;
+    font-size: 11px;
+    font-weight: 600;
+    border-radius: 8px 8px 0 0;
+    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Helvetica Neue', Arial, sans-serif;
+}
+
+#editor-container [data-slate-editor] pre code {
+    background: transparent !important;
+    padding: 0 !important;
+    font-size: inherit !important;
+}
+
 /* 预览区 */
 .preview-pane {
     width: 0;