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## 0.37.0

**`(feat):`** Discriminated unions are now forward-compatible. Each generated `enum` carries
`#[non_exhaustive]` and a final `__Unknown(serde_json::Value)` variant marked
`#[serde(untagged)]`. Unknown discriminant values (e.g. variants introduced
server-side after this SDK was generated) deserialize into `__Unknown`
instead of erroring, preserving the raw JSON payload for inspection and
round-trip serialization.

Forward-compatible unions can no longer derive `Eq`/`Hash` because
`serde_json::Value` doesn't implement them. `PartialEq` is still derived.