refactor: overhaul UI for streamlined user experience

Redesign navigation, home overview, user portrait, and valuation pages
with improved functionality and responsive design.

Co-authored-by: null <4804959+fnvtk@users.noreply.github.com>

app/database-structure/page.tsx

@@ -0,0 +1,10 @@
+import { DatabaseStructureViewer } from "@/components/data-integration/database-structure-viewer"
+
+export default function DatabaseStructurePage() {
+  return (
+    <div className="container mx-auto py-6">
+      <h1 className="text-2xl font-bold mb-6">数据库结构查看器</h1>
+      <DatabaseStructureViewer />
+    </div>
+  )
+}