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## 5.4.0-rc.1

**`(fix):`** Fix `auth: any` with OAuth + header auth schemes (e.g. API key):

* Header auth parameters are now included in the generated client constructor (previously silently dropped when OAuth was present)
* Header auth parameters are passed through to the client wrapper (previously missing, causing a runtime `TypeError`)
* Header auth types are made optional when alongside OAuth, with conditional header setting
* The client can now be instantiated with just a header auth credential (e.g. `api_key`) without requiring OAuth credentials or a bearer token