* fix(decisions): log every request field the caller sent on /v1/systemone and /v1/decisions
* fix(decisions): serialize the logged request with model_dump_json so no mutable dict is built
* refactor(decisions): drop the state-only messages pick in function_setup, prepare_call logs the request
* fix(decisions): return the single logged message so no mutable list type is annotated
* fix(decisions): log the caller's raw request fields before validation so a rejected request is still recorded
* fix(decisions): serialize the raw request fields with pydantic_core so question objects and mapping proxies log as JSON
* fix(decisions): log the caller request at the SDK entry so requests rejected before prepare_call are recorded too
* test(decisions): assert the exact BadRequestError for the rejected-questions case
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Co-authored-by: devin-ai-integration[bot] <158243242+devin-ai-integration[bot]@users.noreply.github.com>
