open_ai: Use proper type for Responses API `input` (#46526)
This PR makes it so we use a proper type for the Responses API `input`
rather than a `serde_json::Value`.
It should have never used `serde_json::Value` to begin with.
Release Notes:
- N/A
c6a38f2cfbMarshall Bowers committed on 1/10/2026, 5:40:20 PM· committed by GitHubparent73d9353