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/Policy/__Tests/StellaOps.Policy.Scoring.Tests/Fixtures/hashing/example-receipt-input.json

@@ -0,0 +1 @@
+{"baseVector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H","computedAt":"2025-12-01T00:00:00Z","evidence":["cas://evidence/sha256:abc"],"policyId":"pol-v4-001","tenantId":"tenant-a","vulnId":"CVE-2025-0001"}

src/Policy/__Tests/StellaOps.Policy.Scoring.Tests/Fixtures/hashing/example-receipt-input.sha256

@@ -0,0 +1 @@
+4de79d5af28ec27a7754e6be6acdb99c36d1fe5792984a7fdb67e98934097142  example-receipt-input.json