A /v1/responses request against the built-in codex/ provider does an
openai-responses -> openai-responses passthrough (CodexExecutor.transformRequest
returns the body early for _nativeCodexPassthrough). It forwarded client-only
fields verbatim and the Codex upstream rejected them with 400 Unsupported
parameter: prompt_cache_retention / safety_identifier / user — breaking Factory
Droid (which injects all three). The chat-completions path already strips these
(base.ts #1884, openai-responses translator #2770) but the passthrough skips
translation. Strip the three fields in the shared block before the passthrough
return; user is removed unconditionally since Codex /responses always rejects it.
Co-authored-by: tycronk20 <tycronk20@users.noreply.github.com>
57e7049d5c