docs: clarify sentence feedback context

docs/superpowers/specs/2026-04-25-english-speaking-report-pipeline-design.md

@@ -66,7 +66,9 @@ The sentence feedback evaluator input is:
 }
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-The conversation history for round N includes the prior conversation and the latest student turn being evaluated. It should not include the AI reply after the latest student turn, because that reply is not context the student had when speaking.
+The conversation history for round N includes only dialogue text: prior AI/student turns and the latest student turn being evaluated. It should not include any previous rounds' Azure scores, previous sentence feedback, or the AI reply after the latest student turn. Previous scores and feedback are not needed for `DetailedReport`; they would bias the per-turn comment away from the student's current utterance.
+
+The only pronunciation scores passed to the sentence feedback evaluator are the Azure scores for the latest student turn.
 
 The evaluator output is: