Add unit tests for RancherHubConnector and various exporters

- Implemented tests for RancherHubConnector to validate fetching documents, handling errors, and managing state.
- Added tests for CsafExporter to ensure deterministic serialization of CSAF documents.
- Created tests for CycloneDX exporters and reconciler to verify correct handling of VEX claims and output structure.
- Developed OpenVEX exporter tests to confirm the generation of canonical OpenVEX documents and statement merging logic.
- Introduced Rust file caching and license scanning functionality, including a cache key structure and hash computation.
- Added sample Cargo.toml and LICENSE files for testing Rust license scanning functionality.

src/__Libraries/StellaOps.Cryptography.Kms/FileKmsOptions.cs

@@ -16,12 +16,12 @@ public sealed class FileKmsOptions
     public required string Password { get; set; }
 
     /// <summary>
-    /// Signing algorithm identifier (default ED25519).
+    /// Signing algorithm identifier (default ES256).
     /// </summary>
     public string Algorithm { get; set; } = KmsAlgorithms.Es256;
 
     /// <summary>
     /// PBKDF2 iteration count for envelope encryption.
     /// </summary>
-    public int KeyDerivationIterations { get; set; } = 100_000;
+    public int KeyDerivationIterations { get; set; } = 600_000;
 }