[BUG][dart-dio]: EnumClass conflict when using 'name' in a enum component

[epou]

Fixes #20910

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[epou]

I was having doubts about implementing the fix by changing the mustache code, so all the enum options are treated the same or overriding the java code to only target those enum values that are equal to name:

In file: modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/DartDioClientCodegen.java

    @Override
    public String toEnumVarName(String value, String datatype) {
         String name = super.toEnumVarName(value, datatype);

         // Fix for Dart (using built_value):
         // The issue is caused by using "name" as an enum value name,
         // which conflicts with the built-in "name" property of EnumClass.
         if (SERIALIZATION_LIBRARY_BUILT_VALUE.equals(library) && "name".equals(name)) {
             name = name + "Attr";
         }
         return name;
     }

I see goods and bads for each option. I'd love to hear opinions

[wing328]

thanks for the PR

can you please pm me via Slack when you've time to discuss this?

https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA