feat(EncodeType): Enum zur Klassifizierung von Kodierungstypen erstellt.

- Erweiterungsmethoden hinzugefügt, um zu versuchen, String mit out-keyworld zu dekodieren.

- Erweiterungsmethode hinzugefügt, um den Typ des Kodierungstyps des dekodierten String-Arrays zu finden.

EnvelopeGenerator.Application/EncodeType.cs

@@ -0,0 +1,9 @@
+namespace EnvelopeGenerator.Application
+{
+    public enum EncodeType
+    {
+        EnvelopeReceiver,
+        ReadOnly,
+        Undefined
+    }
+}

EnvelopeGenerator.Application/EnvelopeGeneratorExtensions.cs

@@ -68,6 +68,26 @@ namespace EnvelopeGenerator.Application
             return input.IndexOf('=') == -1; // No padding allowed except at the end
         }
 
+        public static bool TryDecode(this string encoded, out string[] decoded)
+        {
+            if (!encoded.IsBase64String())
+            {
+                decoded = Array.Empty<string>();
+                return false;
+            }
+            byte[] bytes = Convert.FromBase64String(encoded);
+            string decodedString = Encoding.UTF8.GetString(bytes);
+            decoded = decodedString.Split(new string[] { "::" }, StringSplitOptions.None);
+            return true;
+        }
+
+        public static EncodeType GetEncodeType(string[] decoded) => decoded.Length switch
+        {
+            2 => EncodeType.EnvelopeReceiver,
+            3 => EncodeType.ReadOnly,
+            _ => EncodeType.Undefined,
+        };
+        
         /// <summary>
         /// Decodes the envelope receiver ID and extracts the envelope UUID and receiver signature.
         /// </summary>
@@ -80,7 +100,7 @@ namespace EnvelopeGenerator.Application
                 return (null, null);
             }
             byte[] bytes = Convert.FromBase64String(envelopeReceiverId);
-            string decodedString = System.Text.Encoding.UTF8.GetString(bytes);
+            string decodedString = Encoding.UTF8.GetString(bytes);
             string[] parts = decodedString.Split(new string[] { "::" }, StringSplitOptions.None);
 
             if (parts.Length > 1)