Add support for ГОСТ Р 34.10 digital signatures

- Implemented the GostKeyValue class for handling public key parameters in ГОСТ Р 34.10 digital signatures.
- Created the GostSignedXml class to manage XML signatures using ГОСТ 34.10, including methods for computing and checking signatures.
- Developed the GostSignedXmlImpl class to encapsulate the signature computation logic and public key retrieval.
- Added specific key value classes for ГОСТ Р 34.10-2001, ГОСТ Р 34.10-2012/256, and ГОСТ Р 34.10-2012/512 to support different signature algorithms.
- Ensured compatibility with existing XML signature standards while integrating ГОСТ cryptography.

src/__Libraries/StellaOps.Cryptography.Plugin.CryptoPro/CryptoProGostKeyOptions.cs

@@ -11,6 +11,11 @@ public sealed class CryptoProGostKeyOptions
 
     public string Algorithm { get; set; } = SignatureAlgorithms.GostR3410_2012_256;
 
+    /// <summary>
+    /// Wire format emitted by the signer. Defaults to DER (ASN.1 sequence). Set to Raw for (s || r).
+    /// </summary>
+    public GostSignatureFormat SignatureFormat { get; set; } = GostSignatureFormat.Der;
+
     /// <summary>
     /// Optional CryptoPro provider name (defaults to standard CSP).
     /// </summary>
@@ -21,6 +26,11 @@ public sealed class CryptoProGostKeyOptions
     /// </summary>
     public string? ContainerName { get; set; }
 
+    /// <summary>
+    /// Set to true when the container lives in the machine key store.
+    /// </summary>
+    public bool UseMachineKeyStore { get; set; }
+
     /// <summary>
     /// Thumbprint of the certificate that owns the CryptoPro private key.
     /// </summary>
@@ -45,6 +55,8 @@ public sealed class CryptoProGostKeyOptions
             CertificateThumbprint = CertificateThumbprint,
             SubjectName = SubjectName,
             CertificateStoreLocation = CertificateStoreLocation,
-            CertificateStoreName = CertificateStoreName
+            CertificateStoreName = CertificateStoreName,
+            UseMachineKeyStore = UseMachineKeyStore,
+            SignatureFormat = SignatureFormat
         };
 }