Preserve context across conversation intents (V-542)

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cmd/mavend/voice.go

@@ -555,10 +555,17 @@ func (h *reactiveHandler) replySystem(ctx context.Context, dec router.Decision)
 // history lists. Shared by chatHistory and rememberTurn (clarify.go) so the
 // same session is described the same way in both places.
 func sessionAsTurn(s *dialogue.Session) dialogue.Turn {
+	text := s.Utterance
+	if text == "" {
+		// Compatibility with a session blob written before Utterance became a
+		// first-class field. Slots.Text was the old transcript by convention
+		// for query/chat/system turns, and is still better than dropping it.
+		text = s.Slots.Text
+	}
 	return dialogue.Turn{
 		Intent: s.Intent,
 		Slots:  s.Slots,
-		Text:   s.Slots.Text,
+		Text:   text,
 	}
 }
 
@@ -574,11 +581,12 @@ func (h *reactiveHandler) chatHistory(ctx context.Context) []dialogue.Turn {
 	if prev == nil {
 		return nil
 	}
-	// History already includes the immediate prior turn (set by the dialogue
-	// merge in runTurn's step 6, above), plus up to 3 more from deeper history.
-	out := make([]dialogue.Turn, 0, 1+len(prev.History))
-	out = append(out, sessionAsTurn(prev))
-	out = append(out, prev.History...)
+	// rememberTurn runs before the action so query handlers can bind candidate
+	// lists to the current session. Therefore prev is the CURRENT turn here;
+	// its History is precisely the prior transcript. Adding sessionAsTurn(prev)
+	// would hand the model the current utterance twice.
+	out := make([]dialogue.Turn, len(prev.History))
+	copy(out, prev.History)
 	return out
 }