Add tests for SBOM generation determinism across multiple formats

- Created `StellaOps.TestKit.Tests` project for unit tests related to determinism.
- Implemented `DeterminismManifestTests` to validate deterministic output for canonical bytes and strings, file read/write operations, and error handling for invalid schema versions.
- Added `SbomDeterminismTests` to ensure identical inputs produce consistent SBOMs across SPDX 3.0.1 and CycloneDX 1.6/1.7 formats, including parallel execution tests.
- Updated project references in `StellaOps.Integration.Determinism` to include the new determinism testing library.

docs2/observability-vuln-telemetry.md

@@ -0,0 +1,22 @@
+# Vuln explorer telemetry
+
+Purpose
+- Define metrics, logs, traces, and dashboards for vulnerability triage.
+
+Planned metrics (pending final identifiers)
+- findings_open_total
+- mttr_seconds
+- triage_actions_total
+- report_generation_seconds
+
+Planned logs
+- Fields: findingId, artifactId, advisoryId, policyVersion, actor, actionType.
+- Deterministic JSON with correlation IDs.
+
+Planned traces
+- Spans for triage actions and report generation.
+- Sampling follows global tracing defaults; errors always sampled.
+
+Assets and hashes
+- Capture metrics, logs, traces, and dashboard exports with SHA256SUMS.
+- Store assets under docs/assets/vuln-explorer/ once available.