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## 3.11.0

**`(feat):`** Add support for three-state nullable fields in PATCH requests via `collapse-optional-nullable` config.
When enabled, optional nullable fields use `OptionalNullable<T>` to distinguish between omitted fields,
explicit null values, and actual values. This enables proper PATCH request semantics for APIs that need
to differentiate between "not specified" and "set to null".

```yaml
customConfig:
  collapse-optional-nullable: true
```

Generated usage:

```java
UpdateRequest.builder()
    .fieldName(OptionalNullable.absent())    // Omit field
    .anotherField(OptionalNullable.ofNull()) // Clear field
    .valueField(OptionalNullable.of("value")) // Set value
    .build();
```