* fix(responses): replay the original Responses item order, phase, and boundaries on the next chat turn
* fix(responses): keep tool-call-only stream content empty and drop unreachable replay guards
* fix(responses): reject an assistant phase OpenAI does not define unless drop_params is set
* fix(responses): keep other providers' reasoning and stream output unchanged and fall back on records that do not fit
* fix(responses): label a structured output turn with its returned message's phase and keep lone surrogates from failing the checksum
* fix(responses): leave a turn without a phase when its content message cannot be read
* test(responses): add black box tests for chat turn history replay
* test(responses): expect the replay record on bridged chat replies
* test(responses): expect the replay record in bridged chat translation cases
* fix(streaming): keep the served service tier on the finish chunk the stream adds
* test(responses): read the expected chat message without JSON validation so the replay matcher stays
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Co-authored-by: mateo-berri <277851410+mateo-berri@users.noreply.github.com>
