Add capabilities.

Sources/Packages/Sources/SmartCardSecretKit/SmartCardSecret.swift

@@ -12,6 +12,12 @@ extension SmartCard {
         public let keySize: Int
         public let requiresAuthentication: Bool = false
         public let publicKey: Data
+        public let capabilities: Set<KeyCapabilities>
+
+        public enum KeyCapabilities: Sendable {
+            case signature
+            case encryption
+        }
 
     }
 

Sources/Packages/Sources/SmartCardSecretKit/SmartCardStore.swift

@@ -170,7 +170,14 @@ extension SmartCard.Store {
             let publicKeySecRef = SecKeyCopyPublicKey(publicKeyRef)!
             let publicKeyAttributes = SecKeyCopyAttributes(publicKeySecRef) as! [CFString: Any]
             let publicKey = publicKeyAttributes[kSecValueData] as! Data
-            return SmartCard.Secret(id: tokenID, name: name, algorithm: algorithm, keySize: keySize, publicKey: publicKey)
+            var capabilities: Set<SmartCard.Secret.KeyCapabilities> = []
+            if ($0[kSecAttrCanSign] as? Bool) == true {
+                capabilities.insert(.signature)
+            }
+            if ($0[kSecAttrCanEncrypt] as? Bool) == true && ($0[kSecAttrCanDecrypt] as? Bool) == true {
+                capabilities.insert(.encryption)
+            }
+            return SmartCard.Secret(id: tokenID, name: name, algorithm: algorithm, keySize: keySize, publicKey: publicKey, capabilities: capabilities)
         }
         state.secrets.append(contentsOf: wrapped)
     }