v1.21.0

[1.21.0] — 2026-08-04
Added

#[MapPropertyName] now accepts aliases — #[MapPropertyName('user_id', 'userId', 'uid')] tries each input key in order, first one present wins. Serialization still uses the first alias, unchanged from before.
#[MapInputName] / #[MapOutputName] — map hydration and serialization keys independently, for APIs migrating a field name over time (accept the old key on input, already emit the new key on output). #[MapInputName] also accepts aliases. Cannot be combined with #[MapPropertyName] on the same property.
    Roundtrip invariant preserved: whenever the output key diverges from the declared input names, it's automatically accepted as a fallback input alias too, so from($dto->toArray()) keeps working.
    #[RejectUnknownKeys] treats every alias and the output key as known.
Documentation: see [#[MapPropertyName]](https://std-out.github.io/simple-data-objects/attributes/map-property-name) and [#[MapInputName] / #[MapOutputName]](https://std-out.github.io/simple-data-objects/attributes/map-input-output-name).

Full Changelog: v1.20.0...v1.21.0