refactor: RHI抽象层测试支持参数化

- 将RHITestFixture改为TestWithParam<RHIType>，支持D3D12和OpenGL双后端
- 重构RHIFactory.cpp的include结构，修复OpenGL设备创建
- 在CMakeLists.txt中添加XCENGINE_SUPPORT_OPENGL宏定义
- 更新engine/CMakeLists.txt和tests/RHI/unit/CMakeLists.txt
- 将所有TEST_F改为TEST_P以支持参数化测试

测试结果: 138 tests (D3D12: 58 passed / OpenGL: 48 passed)

tests/RHI/unit/test_shader.cpp

@@ -3,52 +3,52 @@
 
 using namespace XCEngine::RHI;
 
-TEST_F(RHITestFixture, Shader_Compile_EmptyDesc_ReturnsNullptr) {
+TEST_P(RHITestFixture, Shader_Compile_EmptyDesc_ReturnsNullptr) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_GetType_WithNullShader) {
+TEST_P(RHITestFixture, Shader_GetType_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_IsValid_WithNullShader) {
+TEST_P(RHITestFixture, Shader_IsValid_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_Bind_WithNullShader) {
+TEST_P(RHITestFixture, Shader_Bind_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_SetInt_WithNullShader) {
+TEST_P(RHITestFixture, Shader_SetInt_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_SetFloat_WithNullShader) {
+TEST_P(RHITestFixture, Shader_SetFloat_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_SetVec3_WithNullShader) {
+TEST_P(RHITestFixture, Shader_SetVec3_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_SetVec4_WithNullShader) {
+TEST_P(RHITestFixture, Shader_SetVec4_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_SetMat4_WithNullShader) {
+TEST_P(RHITestFixture, Shader_SetMat4_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }
 
-TEST_F(RHITestFixture, Shader_GetNativeHandle_WithNullShader) {
+TEST_P(RHITestFixture, Shader_GetNativeHandle_WithNullShader) {
     RHIShader* shader = GetDevice()->CompileShader({});
     EXPECT_EQ(shader, nullptr);
 }