Fix build and code structure improvements. New but essential UI functionality. CI improvements. Documentation improvements. AI module improvements.

src/__Libraries/StellaOps.ReachGraph/Signing/IReachGraphKeyStore.cs

@@ -0,0 +1,45 @@
+// Licensed to StellaOps under the AGPL-3.0-or-later license.
+
+namespace StellaOps.ReachGraph.Signing;
+
+/// <summary>
+/// Key store abstraction for ReachGraph signing operations.
+/// Wraps the underlying cryptographic key management (Attestor, Signer module, etc.).
+/// </summary>
+public interface IReachGraphKeyStore
+{
+    /// <summary>
+    /// Sign data with the specified key.
+    /// </summary>
+    /// <param name="keyId">The key identifier.</param>
+    /// <param name="data">The data to sign (typically PAE-encoded).</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>The signature bytes.</returns>
+    Task<byte[]> SignAsync(string keyId, byte[] data, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Verify a signature with the specified key.
+    /// </summary>
+    /// <param name="keyId">The key identifier.</param>
+    /// <param name="data">The data that was signed.</param>
+    /// <param name="signature">The signature to verify.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>True if signature is valid, false otherwise.</returns>
+    Task<bool> VerifyAsync(string keyId, byte[] data, byte[] signature, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Check if a key exists and is available for signing.
+    /// </summary>
+    /// <param name="keyId">The key identifier.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>True if key exists and can sign, false otherwise.</returns>
+    Task<bool> CanSignAsync(string keyId, CancellationToken cancellationToken = default);
+
+    /// <summary>
+    /// Check if a key exists and is available for verification.
+    /// </summary>
+    /// <param name="keyId">The key identifier.</param>
+    /// <param name="cancellationToken">Cancellation token.</param>
+    /// <returns>True if key exists and can verify, false otherwise.</returns>
+    Task<bool> CanVerifyAsync(string keyId, CancellationToken cancellationToken = default);
+}