docs: update core and debug API docs

docs/api/core/refcounted/GetRefCount.md

@@ -12,28 +12,36 @@ uint32_t GetRefCount() const;
 
 **返回：** `uint32_t` - 当前引用计数
 
+**线程安全：** ✅
+
 **复杂度：** O(1)
 
 **示例：**
 
 ```cpp
 #include <XCEngine/Core/RefCounted.h>
+#include <cstdio>
 
-class MyObject : public RefCounted {
+class MyObject : public XCEngine::Core::RefCounted {
 public:
     void Debug() {
         printf("RefCount: %u\n", GetRefCount());
     }
 };
 
-MyObject* obj = new MyObject();
-printf("After create: %u\n", obj->GetRefCount());  // 1
-
-obj->AddRef();
-printf("After AddRef: %u\n", obj->GetRefCount());  // 2
-
-obj->Release();
-printf("After Release: %u\n", obj->GetRefCount()); // 1
+int main() {
+    MyObject* obj = new MyObject();
+    printf("After create: %u\n", obj->GetRefCount());
+    
+    obj->AddRef();
+    printf("After AddRef: %u\n", obj->GetRefCount());
+    
+    obj->Release();
+    printf("After Release: %u\n", obj->GetRefCount());
+    
+    obj->Release();
+    return 0;
+}
 ```
 
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