feat: app 端 ui 设计完成

wei_ai_app/lib/widgets/tab_content_layout.dart

@@ -0,0 +1,29 @@
+import 'package:flutter/material.dart';
+
+class TabContentLayout extends StatelessWidget {
+  final Widget child;
+  final bool applyTopPadding;
+  final bool applyBottomPadding;
+
+  const TabContentLayout({
+    super.key,
+    required this.child,
+    this.applyTopPadding = true,
+    this.applyBottomPadding = false, // Usually managed solely by the glass nav height inside the list, but let's see.
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    // Since extendBodyBehindAppBar is true, we don't need extra padding
+    // The body naturally starts from top, but we just need minimal spacing
+    
+    return Padding(
+      padding: EdgeInsets.only(
+        top: 0, // Content starts naturally below AppBar
+        // We don't necessarily pad bottom here if we want content to scroll behind bottom nav,
+        // but for fixed elements (like Discovery Filter bar), we might need structure.
+      ),
+      child: child,
+    );
+  }
+}