feat(zastava): add evidence locker plan and schema examples

- Introduced README.md for Zastava Evidence Locker Plan detailing artifacts to sign and post-signing steps.
- Added example JSON schemas for observer events and webhook admissions.
- Updated implementor guidelines with checklist for CI linting, determinism, secrets management, and schema control.
- Created alert rules for Vuln Explorer to monitor API latency and projection errors.
- Developed analytics ingestion plan for Vuln Explorer, focusing on telemetry and PII guardrails.
- Implemented Grafana dashboard configuration for Vuln Explorer metrics visualization.
- Added expected projection SHA256 for vulnerability events.
- Created k6 load testing script for Vuln Explorer API.
- Added sample projection and replay event data for testing.
- Implemented ReplayInputsLock for deterministic replay inputs management.
- Developed tests for ReplayInputsLock to ensure stable hash computation.
- Created SurfaceManifestDeterminismVerifier to validate manifest determinism and integrity.
- Added unit tests for SurfaceManifestDeterminismVerifier to ensure correct functionality.
- Implemented Angular tests for VulnerabilityHttpClient and VulnerabilityDetailComponent to verify API interactions and UI rendering.

src/Scanner/__Tests/StellaOps.Scanner.Worker.Tests/SurfaceManifestStageExecutorTests.cs

@@ -51,7 +51,8 @@ public sealed class SurfaceManifestStageExecutorTests
             NullLogger<SurfaceManifestStageExecutor>.Instance,
             hash,
             new NullRubyPackageInventoryStore(),
-            new DeterminismContext(true, DateTimeOffset.Parse("2024-01-01T00:00:00Z"), 1337, true, 1));
+            new DeterminismContext(true, DateTimeOffset.Parse("2024-01-01T00:00:00Z"), 1337, true, 1),
+            new DeterministicDsseEnvelopeSigner());
 
         var context = CreateContext();
 
@@ -89,7 +90,8 @@ public sealed class SurfaceManifestStageExecutorTests
             NullLogger<SurfaceManifestStageExecutor>.Instance,
             hash,
             new NullRubyPackageInventoryStore(),
-            new DeterminismContext(false, DateTimeOffset.UnixEpoch, null, false, null));
+            new DeterminismContext(false, DateTimeOffset.UnixEpoch, null, false, null),
+            new DeterministicDsseEnvelopeSigner());
 
         var context = CreateContext();
         PopulateAnalysis(context);