Add comprehensive security tests for OWASP A02, A05, A07, and A08 categories

- Implemented tests for Cryptographic Failures (A02) to ensure proper handling of sensitive data, secure algorithms, and key management.
- Added tests for Security Misconfiguration (A05) to validate production configurations, security headers, CORS settings, and feature management.
- Developed tests for Authentication Failures (A07) to enforce strong password policies, rate limiting, session management, and MFA support.
- Created tests for Software and Data Integrity Failures (A08) to verify artifact signatures, SBOM integrity, attestation chains, and feed updates.

src/__Libraries/StellaOps.Replay.Core/ReplayManifest.cs

@@ -34,6 +34,14 @@ public sealed class ReplayScanMetadata
     [JsonPropertyName("policyDigest")]
     public string? PolicyDigest { get; set; }
 
+    /// <summary>
+    /// Content-addressed digest of the active score policy YAML for reproducibility.
+    /// Format: "sha256:{hex}" computed over canonical JSON of the score policy.
+    /// </summary>
+    [JsonPropertyName("scorePolicyDigest")]
+    [JsonIgnore(Condition = JsonIgnoreCondition.WhenWritingNull)]
+    public string? ScorePolicyDigest { get; set; }
+
     [JsonPropertyName("feedSnapshot")]
     public string? FeedSnapshot { get; set; }