feat: 步骤4提取产品数据改用智能体hz4th_editor执行

- 步骤4调用 openclaw agent --agent hz4th_editor --message 执行提取任务
- 新增任务文本模板(config/agent_task_template.txt)，支持变量填充
- /process页面新增模板编辑面板，可查看/编辑/保存/预览模板
- 模板变量: {{product_name}} {{category}} {{subcategory}} {{library_results}} {{internet_results}}
- 新增API: GET/POST /api/process/agent-template, POST /api/process/agent-template/preview

static/css/process.css

@@ -350,4 +350,55 @@
     .steps-progress {
         flex-wrap: wrap;
     }
-}
+}
+/* 智能体任务模板区域 */
+.template-section .panel-header {
+    display: flex;
+    justify-content: space-between;
+    align-items: center;
+}
+
+.template-actions {
+    display: flex;
+    gap: 8px;
+}
+
+.template-info {
+    background: #f0f4ff;
+    border: 1px solid #c7d2fe;
+    border-radius: 8px;
+    padding: 12px 16px;
+    margin-bottom: 15px;
+    font-size: 13px;
+    color: #4338ca;
+}
+
+.template-info p {
+    margin: 4px 0;
+}
+
+.template-info code {
+    background: #e0e7ff;
+    padding: 1px 5px;
+    border-radius: 3px;
+    font-size: 12px;
+    color: #3730a3;
+}
+
+.template-editor {
+    width: 100%;
+    font-family: 'Courier New', monospace;
+    font-size: 13px;
+    line-height: 1.5;
+    padding: 12px;
+    border: 1px solid #d1d5db;
+    border-radius: 8px;
+    resize: vertical;
+    background: #fafafa;
+}
+
+.template-editor:focus {
+    outline: none;
+    border-color: #667eea;
+    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
+}