Refactor allocation types and improve memory management

This commit renames `AllocationType` to `AllocationOption` across multiple files, enhancing clarity in memory allocation practices. Key updates include:
- Modifications to the `UnsafeArray`, `ParallelNoiseBenchmark`, `Arena`, and `DynamicArena` classes to utilize the new `AllocationOption`.
- Refactoring of the `AllocationManager` and `HashMapHelper` classes to support the new allocation strategy.
- Removal of the `Misaki.HighPerformance.Mathematics` project reference, indicating a restructuring of dependencies.
- Introduction of a new `MathUtilities` class for calculating the smallest power of two, aiding memory allocation strategies.

These changes collectively improve code maintainability and clarity in memory management.

Misaki.HighPerformance.Unsafe/Buffer/Arena .cs

@@ -30,7 +30,7 @@ public unsafe struct Arena : IDisposable
     /// <param name="alignSize">Defines the alignment requirement for the allocated memory.</param>
     /// <returns>A pointer to the allocated memory block or null if the allocation cannot be fulfilled.</returns>
     /// <exception cref="ObjectDisposedException">Thrown if the arena has been disposed.</exception>
-    public void* Allocate(uint size, uint alignSize, AllocationType allocationType)
+    public void* Allocate(uint size, uint alignSize, AllocationOption allocationType)
     {
         ObjectDisposedException.ThrowIf(_disposed, this);
 
@@ -41,9 +41,9 @@ public unsafe struct Arena : IDisposable
         }
 
         _offset = offset + size;
-        var ptr = (byte*)_buffer + offset;
+        var ptr = _buffer + offset;
 
-        if (allocationType == AllocationType.Clear)
+        if (allocationType == AllocationOption.Clear)
         {
             MemClear(ptr, size);
         }