PooledContext removal - continuation. GpuKernelLease prepared for removal.

PerfectNumbers.Core/MersenneNumberTester.cs

@@ -149,8 +149,8 @@ public sealed class MersenneNumberTester(
 
 		var gpuLease = GpuKernelPool.Rent();
 		var accelerator = SharedGpuContext.Accelerator;
-		var stream = gpuLease.Stream;
-		var orderKernel = gpuLease.OrderKernel!;
+		var stream = accelerator.CreateStream();
+		var orderKernel = GpuKernelLease.OrderKernel!;
 
 		// Guard long-running kernels by chunking the warm-up across batches.
 		// Reuse the same ScanBatchSize knob used for scanning.
@@ -196,6 +196,7 @@ public sealed class MersenneNumberTester(
 			qBuffer.Dispose();
 		}
 
+		stream.Dispose();
 		gpuLease.Dispose();
 		uInt128Pool.Return(qs);
 	}