Moved BindingGenerator from gen html project. It makes more sense here.

Sources/HRW/Internal/AppError.swift

@@ -8,7 +8,9 @@
 
 import Foundation
 
-final class AppError: LocalizedError, Sendable {
+final class AppError: LocalizedError, Sendable, CustomStringConvertible {
+    var description: String { get {message}}
+    
     
     let message: String
     
@@ -28,4 +30,13 @@ final class AppError: LocalizedError, Sendable {
             return message
         }
     }
+    
+    /// A localized message describing the reason for the failure.
+    var failureReason: String? { get { message } }
+
+    var localizedDescription: String? {
+        get {
+            message
+        }
+    }
 }