feat: Wave 2 - API org isolation + factory.html + insights.html

- Add org_id auto-population to articles.py, publishing.py, metrics.py
- Add org_id filtering to search_rankings.py geo endpoints
- Add org_id to calendar.py create/update/delete endpoints
- Add org_id to tasks.py create endpoints
- Create factory.html content pipeline page (3-tab: 待创作/进行中/待审查)
- Create insights.html analytics page (4-tab: 概览/搜索排名/GEO/平台对比)

platform/frontend/uni-nav.js

@@ -121,23 +121,20 @@
 
   function getCurrentPage() {
     var path = window.location.pathname;
-    if (path === '/index.html') return 'dashboard';
+    if (path === '/index.html') return 'workspace';
     var m = path.match(/\/(\w+)\.html/);
-    return m ? m[1] : 'dashboard';
+    return m ? m[1] : 'workspace';
   }
 
   function navItems(isAdmin) {
     var items = [
-      { key: 'dashboard', label: '仪表盘', page: 'index.html' },
-      { key: 'topics', label: '选题', page: 'topics.html' },
-      { key: 'metrics', label: '数据', page: 'metrics.html' },
-      { key: 'calendar', label: '日历', page: 'calendar.html' },
-      { key: 'assets', label: '素材', page: 'assets.html' },
-      { key: 'tasks', label: '任务', page: 'tasks.html' },
-      
+      { key: 'workspace', label: '工作台', page: 'index.html' },
+      { key: 'factory', label: '内容工厂', page: 'factory.html' },
+      { key: 'insights', label: '数据洞察', page: 'insights.html' },
+      { key: 'assets', label: '资产库', page: 'assets.html' },
     ];
     if (isAdmin) {
-      items.push({ key: 'admin', label: '系统', page: 'admin.html', admin: true });
+      items.push({ key: 'admin', label: '系统管理', page: 'admin.html', admin: true });
     }
     return items;
   }