Adresses issues:

• [BUG][JAVA] discriminator ignored during serialization #12777
• Bug: Custom serialization/deserialization using Jackson ObjectMapper is impossible due to ignoring discrimination type getter #22527

Flag added to config:
disableDiscriminatorFieldIgnore -> if true, it ignores, does not creates jakarta @JsonIgnoreProperties in parent class like so:

/**
 * BaseConfiguration
 */
@JsonPropertyOrder({
  BaseConfiguration.JSON_PROPERTY_ID,
  BaseConfiguration.JSON_PROPERTY_TYPE
})
@javax.annotation.Generated(value = "org.openapitools.codegen.languages.JavaClientCodegen", date = "2025-12-10T23:17:17.750816900+01:00[Europe/Warsaw]", comments = "Generator version: 7.18.0-SNAPSHOT")

@JsonTypeInfo(use = JsonTypeInfo.Id.NAME, include = JsonTypeInfo.As.PROPERTY, property = "type", visible = true)
@JsonSubTypes({
  @JsonSubTypes.Type(value = ChildOneConfiguration.class, name = "CHILD_ONE"),
  @JsonSubTypes.Type(value = ChildTwoConfiguration.class, name = "CHILD_TWO"),
})

public class BaseConfiguration {
  public static final String JSON_PROPERTY_ID = "id";
  @javax.annotation.Nullable
  private Long id;

  public static final String JSON_PROPERTY_TYPE = "type";
  @javax.annotation.Nonnull
  private ConfigurationType type;

  public BaseConfiguration() { 
  }

@bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10) @martin-mfg (2023/08)

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