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.

samples/api/scheduler/policy-simulation-status.json

@@ -0,0 +1,29 @@
+{
+  "simulation": {
+    "schemaVersion": "scheduler.policy-run-status@1",
+    "runId": "run:P-7:20251103T153000Z:e4d1a9b2",
+    "tenantId": "tenant-alpha",
+    "policyId": "P-7",
+    "policyVersion": 4,
+    "mode": "simulate",
+    "status": "queued",
+    "priority": "normal",
+    "queuedAt": "2025-11-03T15:30:00Z",
+    "stats": {
+      "components": 0,
+      "rulesFired": 0,
+      "findingsWritten": 0,
+      "vexOverrides": 0
+    },
+    "inputs": {
+      "sbomSet": [
+        "sbom:S-318",
+        "sbom:S-42"
+      ],
+      "captureExplain": true
+    },
+    "metadata": {
+      "source": "console.review"
+    }
+  }
+}