Refactor AllocationManager and enhance debug tracking

Refactored `AllocationManager` to introduce intrusive allocation tracking with `AllocationHeader` structs for debug mode. Added lightweight allocation counters for non-debug mode. Enhanced memory leak detection with detailed stack traces and `MemoryLeakException`.

Simplified `AllocationInfo` by removing the `Allocator` property. Updated `AllocationOption` enum to remove `UnTracked` and clarified documentation.

Improved unsafe collections (`UnsafeArray`, `UnsafeStack`, etc.) with strongly-typed enumerators and better compatibility with `IEnumerable<T>`. Enhanced `UnsafeStack` with a dedicated `Enumerator` struct and consistent constructor parameters.

Refactored `MemoryLeakException` to support detailed allocation info and improved stack trace formatting. Simplified `MemoryUtility` by removing redundant null checks.

Added unit tests for `AllocationManager`, `UnsafeArray`, and `UnsafeStack` to validate memory management and functionality. Updated `Program.cs` with new examples.

Cleaned up namespaces, removed redundant `using` directives, and improved XML documentation. Applied `MethodImplOptions.AggressiveInlining` to performance-critical methods.

Misaki.HighPerformance.LowLevel/Buffer/Stack.cs

@@ -1,4 +1,4 @@
-using System.Runtime.CompilerServices;
+using System.Runtime.CompilerServices;
 
 namespace Misaki.HighPerformance.LowLevel.Buffer;
 
@@ -11,7 +11,7 @@ public unsafe struct Stack : IDisposable
 {
     private const nuint _DEFAULT_SIZE = 1024 * 1024; // 1MB
 
-    public readonly struct Scope : IDisposable
+    public readonly ref struct Scope : IDisposable
     {
         private readonly Stack* _allocator;
         private readonly nuint _originalOffset;