Add determinism tests for verdict artifact generation and update SHA256 sums script

- Implemented comprehensive tests for verdict artifact generation to ensure deterministic outputs across various scenarios, including identical inputs, parallel execution, and change ordering.
- Created helper methods for generating sample verdict inputs and computing canonical hashes.
- Added tests to validate the stability of canonical hashes, proof spine ordering, and summary statistics.
- Introduced a new PowerShell script to update SHA256 sums for files, ensuring accurate hash generation and file integrity checks.

docs/vuln/explorer-overview.md

@@ -1,10 +1,25 @@
-# Archived: Vulnerability Explorer Overview
+# Vulnerability Explorer Overview (Detailed)
 
-This page was consolidated into the canonical guides:
+The Vulnerability Explorer is the evidence-linked triage surface that brings together SBOM facts, advisory/VEX evidence, reachability signals, policy explainability, and operator decisions into a single auditable workflow.
 
-- `docs/20_VULNERABILITY_EXPLORER_GUIDE.md`
-- `docs/15_UI_GUIDE.md`
+This document complements the high-level guide `docs/20_VULNERABILITY_EXPLORER_GUIDE.md` with additional detail and cross-links.
 
-The previous draft has been archived to:
+## Core Objects
 
-- `docs/_archive/vuln/explorer-overview.md`
+- **Finding record:** the current enriched view of a vulnerability for a specific artifact/context (tenant, artifact/image digest, policy version).
+- **History:** append-only state transitions suitable for audit and replay.
+- **Triage actions:** operator actions (assignment, comment, mitigation note, exception request) with provenance.
+- **Evidence references:** stable pointers to evidence objects (SBOM slices, VEX observations/linksets, reachability proofs, explain traces, attestations).
+
+## Key Properties
+
+- **Narrative-first:** default view answers “Can I ship? If not, why? What’s the smallest safe change?”
+- **Proof-linked:** every important fact links to evidence (no “trust the UI”).
+- **Quiet by default, never silent:** suppression/muting is reversible and auditable.
+- **Offline-ready:** evidence bundles are verifiable without online lookups.
+
+## References
+
+- High-level guide: `docs/20_VULNERABILITY_EXPLORER_GUIDE.md`
+- Console operator guide: `docs/15_UI_GUIDE.md`
+- Module dossier: `docs/modules/vuln-explorer/architecture.md`