Add unit tests for SBOM ingestion and transformation

- Implement `SbomIngestServiceCollectionExtensionsTests` to verify the SBOM ingestion pipeline exports snapshots correctly.
- Create `SbomIngestTransformerTests` to ensure the transformation produces expected nodes and edges, including deduplication of license nodes and normalization of timestamps.
- Add `SbomSnapshotExporterTests` to test the export functionality for manifest, adjacency, nodes, and edges.
- Introduce `VexOverlayTransformerTests` to validate the transformation of VEX nodes and edges.
- Set up project file for the test project with necessary dependencies and configurations.
- Include JSON fixture files for testing purposes.

src/Scheduler/__Tests/StellaOps.Scheduler.Models.Tests/PolicyRunModelsTests.cs

@@ -26,8 +26,70 @@ public sealed class PolicyRunModelsTests
         Assert.Equal(JsonValueKind.True, inputs.Environment["sealed"].ValueKind);
         Assert.Equal("internet", inputs.Environment["exposure"].GetString());
         Assert.Equal("global", inputs.Environment["region"].GetString());
-    }
-
+    }
+
+    [Fact]
+    public void PolicySimulationWebhookPayloadFactory_ComputesSucceeded()
+    {
+        var now = DateTimeOffset.UtcNow;
+        var job = CreateJob(PolicyRunJobStatus.Completed, now);
+        var status = PolicyRunStatusFactory.Create(job, now);
+
+        var payload = PolicySimulationWebhookPayloadFactory.Create(status, now);
+
+        Assert.Equal(succeeded, payload.Result);
+        Assert.Equal(status, payload.Simulation);
+        Assert.Null(payload.Reason);
+        Assert.NotNull(payload.LatencySeconds);
+    }
+
+    [Fact]
+    public void PolicySimulationWebhookPayloadFactory_ComputesFailureReason()
+    {
+        var now = DateTimeOffset.UtcNow;
+        var job = CreateJob(PolicyRunJobStatus.Failed, now) with { LastError = timeout };
+        var status = PolicyRunStatusFactory.Create(job, now);
+
+        var payload = PolicySimulationWebhookPayloadFactory.Create(status, now);
+
+        Assert.Equal(failed, payload.Result);
+        Assert.Equal(timeout, payload.Reason);
+    }
+
+    private static PolicyRunJob CreateJob(PolicyRunJobStatus status, DateTimeOffset timestamp)
+    {
+        return new PolicyRunJob(
+            SchemaVersion: SchedulerSchemaVersions.PolicyRunJob,
+            Id: job,
+            TenantId: tenant,
+            PolicyId: policy,
+            PolicyVersion: 1,
+            Mode: PolicyRunMode.Simulate,
+            Priority: PolicyRunPriority.Normal,
+            PriorityRank: 0,
+            RunId: run,
+            RequestedBy: tester,
+            CorrelationId: corr,
+            Metadata: null,
+            Inputs: PolicyRunInputs.Empty,
+            QueuedAt: timestamp,
+            Status: status,
+            AttemptCount: 1,
+            LastAttemptAt: timestamp,
+            LastError: status == PolicyRunJobStatus.Failed ? error : null,
+            CreatedAt: timestamp,
+            UpdatedAt: timestamp,
+            AvailableAt: timestamp,
+            SubmittedAt: timestamp,
+            CompletedAt: status == PolicyRunJobStatus.Completed ? timestamp : null,
+            LeaseOwner: null,
+            LeaseExpiresAt: null,
+            CancellationRequested: status == PolicyRunJobStatus.Cancelled,
+            CancellationRequestedAt: null,
+            CancellationReason: null,
+            CancelledAt: status == PolicyRunJobStatus.Cancelled ? timestamp : null);
+    }
+
     [Fact]
     public void PolicyRunStatus_ThrowsOnNegativeAttempts()
     {