refactor(functional): 统一功能模块命名空间格式

- 将 GFramework.Core.Functional 命名空间统一改为 GFramework.Core.functional
- 更新 AsyncFunctionalExtensions.cs 中的命名空间声明
- 移除不必要的 using 指令，包括 GFramework.Core.Functional 的导入
- 调整测试文件中的命名空间引用以匹配新的命名空间格式
- 确保所有相关文件都使用一致的小写命名空间约定

GFramework.Core.Tests/extensions/AsyncExtensionsTests.cs

@@ -1,6 +1,6 @@
 using System.Diagnostics;
 using GFramework.Core.extensions;
-using GFramework.Core.Functional.Async;
+using GFramework.Core.functional.async;
 using NUnit.Framework;
 
 namespace GFramework.Core.Tests.extensions;

GFramework.Core.Tests/extensions/ResultExtensionsTests.cs

@@ -11,11 +11,11 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-using GFramework.Core.Functional;
+using GFramework.Core.functional;
 using GFramework.Core.functional.result;
 using NUnit.Framework;
 
-namespace GFramework.Core.Tests.Extensions;
+namespace GFramework.Core.Tests.extensions;
 
 /// <summary>
 ///     ResultExtensions 扩展方法测试类

GFramework.Core.Tests/functional/OptionTests.cs

@@ -11,10 +11,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-using GFramework.Core.Functional;
+using GFramework.Core.functional;
 using NUnit.Framework;
 
-namespace GFramework.Core.Tests.Functional;
+namespace GFramework.Core.Tests.functional;
 
 /// <summary>
 ///     Option&lt;T&gt; 类型测试类

GFramework.Core.Tests/functional/ResultTTests.cs

@@ -11,10 +11,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-using GFramework.Core.Functional;
+using GFramework.Core.functional;
 using NUnit.Framework;
 
-namespace GFramework.Core.Tests.Functional;
+namespace GFramework.Core.Tests.functional;
 
 /// <summary>
 ///     Result&lt;A&gt; 泛型类型测试类

GFramework.Core.Tests/functional/ResultTests.cs

@@ -11,10 +11,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-using GFramework.Core.Functional;
+using GFramework.Core.functional;
 using NUnit.Framework;
 
-namespace GFramework.Core.Tests.Functional;
+namespace GFramework.Core.Tests.functional;
 
 /// <summary>
 ///     Result 类型测试类

GFramework.Core/functional/Option.cs

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-namespace GFramework.Core.Functional;
+namespace GFramework.Core.functional;
 
 /// <summary>
 ///     表示可能存在或不存在的值，用于替代 null 引用的函数式编程类型

GFramework.Core/functional/Result.T.cs

@@ -13,7 +13,7 @@
 
 using System.Diagnostics.Contracts;
 
-namespace GFramework.Core.Functional;
+namespace GFramework.Core.functional;
 
 /// <summary>
 ///     表示一个操作的结果，可能是成功值或异常

GFramework.Core/functional/Result.cs

@@ -13,7 +13,7 @@
 
 using System.Diagnostics.Contracts;
 
-namespace GFramework.Core.Functional;
+namespace GFramework.Core.functional;
 
 /// <summary>
 ///     表示一个无值的操作结果，仅包含成功或失败状态

GFramework.Core/functional/async/AsyncFunctionalExtensions.cs

@@ -11,7 +11,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-namespace GFramework.Core.Functional.Async;
+namespace GFramework.Core.functional.async;
 
 /// <summary>
 ///     异步函数式编程扩展方法

GFramework.Core/functional/functions/FunctionExtensions.cs

@@ -12,7 +12,6 @@
 // limitations under the License.
 
 using System.Collections.Concurrent;
-using GFramework.Core.Functional;
 
 namespace GFramework.Core.functional.functions;
 

GFramework.Core/functional/result/ResultExtensions.cs

@@ -12,8 +12,6 @@
 // limitations under the License.
 
 
-using GFramework.Core.Functional;
-
 namespace GFramework.Core.functional.result;
 
 /// <summary>