audit work, fixed StellaOps.sln warnings/errors, fixed tests, sprints work, new advisories

src/Findings/tools/LedgerReplayHarness/HarnessRunner.cs

@@ -1,5 +1,6 @@
 using System.Collections.Concurrent;
 using System.Diagnostics;
+using System.Globalization;
 using System.Text.Json;
 
 namespace LedgerReplayHarness;
@@ -117,7 +118,7 @@ public sealed class HarnessRunner
             cpuPercentMax = 0,
             memoryMbMax = 0,
             status = hashesValid && merkleOk ? "pass" : "fail",
-            timestamp = _timeProvider.GetUtcNow().ToString("O"),
+            timestamp = _timeProvider.GetUtcNow().ToString("O", CultureInfo.InvariantCulture),
             hashSummary = stats.ToReport(),
             merkleRoot = computedRoot,
             merkleExpected = expectedMerkleRoot