Move to Flutter 3.47, use the improvements that come with this (#64)

Reviewed-on: #64

lib/models/oauth_auth_code_response.dart

@@ -1,14 +1,16 @@
 import "package:freezed_annotation/freezed_annotation.dart";
+
 part "oauth_auth_code_response.freezed.dart";
 part "oauth_auth_code_response.g.dart";
 
-@freezed
-abstract class OAuthAuthCodeResponse with _$OAuthAuthCodeResponse {
-  const factory OAuthAuthCodeResponse({
-    required String state,
-    required String codeVerifier,
-    required Uri url,
-  }) = _OAuthAuthCodeResponse;
+@Freezed(toJson: false, fromJson: false)
+@JsonSerializable()
+class const OAuthAuthCodeResponse({
+  required final String state,
+  required final String codeVerifier,
+  required final Uri url,
+}) with _$OAuthAuthCodeResponse {
+  Map<String, Object?> toJson() => _$OAuthAuthCodeResponseToJson(this);
 
   factory OAuthAuthCodeResponse.fromJson(Map<String, Object?> json) =>
       _$OAuthAuthCodeResponseFromJson(json);