feat: 实现Containers、Memory、Threading核心模块及单元测试

- Containers: String, Array, HashMap 容器实现及测试
- Memory: Allocator, LinearAllocator, PoolAllocator, ProxyAllocator, MemoryManager 实现及测试
- Threading: Mutex, SpinLock, ReadWriteLock, Thread, Task, TaskSystem 实现及测试
- 修复Windows平台兼容性: _aligned_malloc, std::hash特化
- 修复构建错误和测试用例问题

tests/memory/test_pool_allocator.cpp

@@ -0,0 +1,83 @@
+#include <gtest/gtest.h>
+#include <XCEngine/Memory/PoolAllocator.h>
+
+using namespace XCEngine::Memory;
+
+namespace {
+
+TEST(PoolAllocator, Allocate) {
+    PoolAllocator allocator(64, 10);
+    
+    void* ptr = allocator.Allocate(32);
+    ASSERT_NE(ptr, nullptr);
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 9u);
+}
+
+TEST(PoolAllocator, AllocateTooLarge) {
+    PoolAllocator allocator(64, 10);
+    
+    void* ptr = allocator.Allocate(128);
+    EXPECT_EQ(ptr, nullptr);
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 10u);
+}
+
+TEST(PoolAllocator, Free) {
+    PoolAllocator allocator(64, 10);
+    
+    void* ptr = allocator.Allocate(32);
+    ASSERT_NE(ptr, nullptr);
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 9u);
+    
+    allocator.Free(ptr);
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 10u);
+}
+
+TEST(PoolAllocator, AllocateAllBlocks) {
+    PoolAllocator allocator(64, 5);
+    
+    void* blocks[5];
+    for (int i = 0; i < 5; ++i) {
+        blocks[i] = allocator.Allocate(32);
+        ASSERT_NE(blocks[i], nullptr);
+    }
+    
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 0u);
+    
+    void* extra = allocator.Allocate(32);
+    EXPECT_EQ(extra, nullptr);
+}
+
+TEST(PoolAllocator, ReuseFreedBlocks) {
+    PoolAllocator allocator(64, 3);
+    
+    void* ptr1 = allocator.Allocate(32);
+    void* ptr2 = allocator.Allocate(32);
+    void* ptr3 = allocator.Allocate(32);
+    
+    allocator.Free(ptr2);
+    EXPECT_EQ(allocator.GetFreeBlockCount(), 1u);
+    
+    void* ptr4 = allocator.Allocate(32);
+    EXPECT_EQ(ptr4, ptr2);
+}
+
+TEST(PoolAllocator, GetBlockSize) {
+    PoolAllocator allocator(64, 10);
+    EXPECT_EQ(allocator.GetBlockSize(), 64u);
+}
+
+TEST(PoolAllocator, GetTotalBlockCount) {
+    PoolAllocator allocator(64, 10);
+    EXPECT_EQ(allocator.GetTotalBlockCount(), 10u);
+}
+
+TEST(PoolAllocator, Contains) {
+    PoolAllocator allocator(64, 10);
+    
+    void* ptr = allocator.Allocate(32);
+    ASSERT_NE(ptr, nullptr);
+    
+    EXPECT_TRUE(allocator.Contains(ptr));
+}
+
+} // namespace