Compilation errors fixed

PerfectNumbers.Core/CycleRemainderStepper.cs

@@ -1,9 +1,10 @@
 using System;
 using System.Numerics;
+using System.Runtime.CompilerServices;
 
 namespace PerfectNumbers.Core;
 
-internal struct CycleRemainderStepper
+public struct CycleRemainderStepper
 {
     private readonly ulong _cycleLength;
     private ulong _previousPrime;
@@ -23,6 +24,7 @@ internal struct CycleRemainderStepper
         _hasState = false;
     }
 
+	[MethodImpl(MethodImplOptions.AggressiveInlining)]
 	public void Reset()
 	{
 		// TODO: Inline this reset at the call sites so the hot loops reuse struct reinitialization

PerfectNumbers.Core/PrimeOrderCalculator.Cpu.cs

@@ -1522,4 +1522,4 @@ internal static partial class PrimeOrderCalculator
 		public readonly long Tertiary = tertiary;
 	}
 }
-}
+

PerfectNumbers.Core/PrimeOrderCalculator.Shared.cs

@@ -5,6 +5,7 @@ using System.Diagnostics;
 using System.Numerics;
 using System.Runtime.CompilerServices;
 using System.Threading;
+using PerfectNumbers.Core.Gpu;
 
 namespace PerfectNumbers.Core;