feat: Add MongoIdempotencyStoreOptions for MongoDB configuration

feat: Implement BsonJsonConverter for converting BsonDocument and BsonArray to JSON

fix: Update project file to include MongoDB.Bson package

test: Add GraphOverlayExporterTests to validate NDJSON export functionality

refactor: Refactor Program.cs in Attestation Tool for improved argument parsing and error handling

docs: Update README for stella-forensic-verify with usage instructions and exit codes

feat: Enhance HmacVerifier with clock skew and not-after checks

feat: Add MerkleRootVerifier and ChainOfCustodyVerifier for additional verification methods

fix: Update DenoRuntimeShim to correctly handle file paths

feat: Introduce ComposerAutoloadData and related parsing in ComposerLockReader

test: Add tests for Deno runtime execution and verification

test: Enhance PHP package tests to include autoload data verification

test: Add unit tests for HmacVerifier and verification logic

src/Graph/__Tests/StellaOps.Graph.Indexer.Tests/GraphOverlayExporterTests.cs

@@ -0,0 +1,49 @@
+using System.IO;
+using System.Linq;
+using StellaOps.Graph.Indexer.Analytics;
+using StellaOps.Graph.Indexer.Ingestion.Sbom;
+
+namespace StellaOps.Graph.Indexer.Tests;
+
+public sealed class GraphOverlayExporterTests
+{
+    [Fact]
+    public async Task ExportAsync_WritesDeterministicNdjson()
+    {
+        var snapshot = GraphAnalyticsTestData.CreateLinearSnapshot();
+        var engine = new GraphAnalyticsEngine(new GraphAnalyticsOptions { MaxPropagationIterations = 3 });
+        var result = engine.Compute(snapshot);
+
+        var tempDir = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("N"));
+        Directory.CreateDirectory(tempDir);
+
+        try
+        {
+            var writer = new FileSystemSnapshotFileWriter(tempDir);
+            var exporter = new GraphOverlayExporter();
+
+            await exporter.ExportAsync(snapshot, result, writer, CancellationToken.None);
+
+            var clustersPath = Path.Combine(tempDir, "overlays", "clusters.ndjson");
+            var centralityPath = Path.Combine(tempDir, "overlays", "centrality.ndjson");
+
+            var clusterLines = await File.ReadAllLinesAsync(clustersPath);
+            var centralityLines = await File.ReadAllLinesAsync(centralityPath);
+
+            Assert.Equal(result.Clusters.Length, clusterLines.Length);
+            Assert.Equal(result.CentralityScores.Length, centralityLines.Length);
+
+            // Ensure deterministic ordering by node id
+            var clusterNodeIds = clusterLines.Select(line => System.Text.Json.JsonDocument.Parse(line).RootElement.GetProperty("node_id").GetString()).ToArray();
+            var sorted = clusterNodeIds.OrderBy(id => id, StringComparer.Ordinal).ToArray();
+            Assert.Equal(sorted, clusterNodeIds);
+        }
+        finally
+        {
+            if (Directory.Exists(tempDir))
+            {
+                Directory.Delete(tempDir, recursive: true);
+            }
+        }
+    }
+}