[scala-http4s] Preserve underscores in enum names

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/AbstractScalaCodegen.java

@@ -551,6 +551,21 @@ protected String formatIdentifier(String name, boolean capitalized) {
 
         return escapeReservedWord(identifier);
     }
+    protected String formatEnumIdentifier(String name) {
+        if (specialCharReplacements.containsKey(name)) {
+            name = specialCharReplacements.get(name);
+        }
+
+        String sanitized = sanitizeName(name);
+
+        // Preserve SCREAMING_SNAKE_CASE enum values
+        if (sanitized.matches("^[A-Z][A-Z0-9_]*$")
+                && !isReservedWord(sanitized)) {
+            return sanitized;
+        }
+
+        return formatIdentifier(sanitized, true);
+    }
 
     protected String stripPackageName(String input) {
         if (!stripPackageName || StringUtils.isEmpty(input) || input.lastIndexOf(".") < 0)

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/ScalaHttp4sClientCodegen.java

@@ -628,7 +628,7 @@ public String toDefaultValue(Schema p) {
     private class EnumEntryLambda extends CustomLambda {
         @Override
         public String formatFragment(String fragment) {
-            return formatIdentifier(fragment, true);
+            return formatEnumIdentifier(fragment);
         }
     }