fix: Improve kb-bilibili-metadata output format

- Wrap result in standard format with success/data/metadata
- Change default headless to False (use API by default)
- Add error handling with structured output
- Improve CLI output readability

skills/kb-bilibili-metadata/bilibili_metadata.py

@@ -98,8 +98,8 @@ def main():
     parser.add_argument(
         '--headless',
         action='store_true',
-        default=True,
-        help='使用无头模式（浏览器，默认开启）'
+        default=False,
+        help='使用无头模式（浏览器，默认关闭，使用API）'
     )
     parser.add_argument(
         '--timeout',
@@ -131,18 +131,34 @@ def main():
             print(f"错误: 不支持的类型 {args.type}")
             sys.exit(1)
         
+        # 包装为标准输出格式
+        output = {
+            "success": True,
+            "data": result,
+            "metadata": {
+                "type": args.type,
+                "id": args.id,
+                "fetched_at": "2024-01-01T00:00:00"
+            }
+        }
+        
         # 输出结果
         if not args.output:
             if args.pretty:
-                print(json.dumps(result, ensure_ascii=False, indent=2))
+                print(json.dumps(output, ensure_ascii=False, indent=2))
             else:
-                print(json.dumps(result, ensure_ascii=False))
+                print(json.dumps(output, ensure_ascii=False))
         
         if args.output:
             print(f"结果已保存到: {args.output}")
         
     except Exception as e:
-        print(f"错误: {e}", file=sys.stderr)
+        error_output = {
+            "success": False,
+            "error": str(e),
+            "error_type": type(e).__name__
+        }
+        print(json.dumps(error_output, ensure_ascii=False, indent=2))
         sys.exit(1)