PrimeOrderCalculator converted to a template.

PerfectNumbers.Core/PerfectNumberConstants.cs

@@ -23,6 +23,7 @@ public static class PerfectNumberConstants
 	public const int ThreadsByAccelerator = 1;
 	public const int ByDivisorStateSaveInterval = 200_000;
 	public const string ByDivisorStateDirectory = "Checks";
+	public const int PollardRhoMilliseconds = 100;
     // TODO: Load these limits from the benchmark-driven configuration so CPU and GPU scans stay aligned with the optimal
     // divisor-cycle datasets we generate offline.
     // TODO: Promote these magic numbers into a runtime profile derived from EvenPerfectBitScanner.Benchmarks so we can retune