fix(task-chat): place a steered yielded reply in its own segment

A steering anchor can split a yielded turn. The authored reply now
renders in the last segment that contains an authored final, not
always in the last populated segment. The settled final-response
choice moves from a nested ternary into a small helper, and the
runner turn's suppressFinal prop is renamed awaitingContinuation,
since it no longer suppresses authored prose.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ui/src/components/TaskChatThread.test.tsx

@@ -3267,6 +3267,70 @@ describe("TaskChatThread runtime transcript selection", () => {
     );
   });
 
+  it("keeps a steered yielded turn's reply in the segment that wrote it", () => {
+    const runId = "steered-interview";
+    nativeTranscriptState.transcriptByRun.set(runId, [
+      assistantEntry("2026-08-25T18:00:02.000Z", "Here is the question card I just posted for you.", "final"),
+      assistantEntry("2026-08-25T18:00:10.000Z", "Folding in the steering note.", "progress"),
+    ]);
+    renderThread({
+      comments: [
+        {
+          id: "steer",
+          companyId: "company-1",
+          issueId: "issue-1",
+          authorType: "user",
+          authorAgentId: null,
+          authorUserId: "user-1",
+          body: "Steering note from the user.",
+          presentation: null,
+          metadata: null,
+          runId: null,
+          consumedByRunId: runId,
+          steeredIntoRunId: runId,
+          conversationAnchorAt: new Date("2026-08-25T18:00:05.000Z"),
+          createdAt: new Date("2026-08-25T18:00:05.000Z"),
+          updatedAt: new Date("2026-08-25T18:00:05.000Z"),
+        },
+      ],
+      onAdd: async () => {},
+      issueStatus: "in_progress",
+      interactions: [
+        {
+          ...questionInteraction("steered-card", "Pick one", "2026-08-25T18:00:03.000Z"),
+          sourceRunId: runId,
+        } as IssueThreadInteraction,
+      ],
+      linkedRuns: [
+        {
+          runId,
+          runtimeMode: "native",
+          status: "succeeded",
+          agentId: "agent-1",
+          agentName: "Runner",
+          adapterType: "paperclip_runner",
+          createdAt: "2026-08-25T18:00:00.000Z",
+          startedAt: "2026-08-25T18:00:00.000Z",
+          finishedAt: "2026-08-25T18:00:20.000Z",
+          resultJson: {
+            nativeResult: {
+              schema: "paperclip.run_result.v1",
+              reportedWorkDisposition: "yielded",
+              summary: "Waiting for Pick one.",
+            },
+          },
+        },
+      ],
+    });
+    const text = container.textContent ?? "";
+    const replyAt = text.indexOf("Here is the question card I just posted");
+    const steerAt = text.indexOf("Steering note from the user.");
+    expect(replyAt).toBeGreaterThanOrEqual(0);
+    expect(steerAt).toBeGreaterThanOrEqual(0);
+    expect(replyAt).toBeLessThan(steerAt);
+    expect(text.split("Here is the question card I just posted")).toHaveLength(2);
+  });
+
   it("keeps a yielded question turn out of the final-response slot", () => {
     nativeTranscriptState.transcriptByRun.set("native-question", [
       assistantEntry("2026-08-25T18:00:01.000Z", "Preparing the verification question.", "progress"),

ui/src/components/TaskChatThread.tsx

@@ -2108,35 +2108,53 @@ export function TaskChatThread(props: TaskChatThreadProps) {
           break;
         }
       }
+      // A yielded turn's authored reply renders once, in the segment that
+      // contains it: the last segment with an authored final, which is where
+      // the whole-run scan found it. A steering anchor can split the turn, so
+      // the last populated segment is not always the right one.
+      const yieldedOptions = {
+        runId: source.id,
+        agentName: meta?.agentName,
+        allowFallback: false,
+        yielded: true,
+        waitSummary: acceptedSummary,
+      };
+      const yieldedResponseSegmentIndex = sourceYieldedResponse
+        ? projectedSegments.findLastIndex(({ parsed }) =>
+            Boolean(paperclipRunnerFinalResponse(parsed, yieldedOptions)))
+        : -1;
+      const settledSegmentFinalResponse = (
+        segmentIndex: number,
+        parsed: readonly TaskChatItem[],
+      ): TaskChatMessageItem | undefined => {
+        if (!sourceIsPaperclipRunner) return undefined;
+        const lastSegment = segmentIndex === lastPopulatedSegmentIndex;
+        if (sourceYielded) {
+          if (!sourceYieldedResponse) return undefined;
+          if (yieldedResponseSegmentIndex === -1) return lastSegment ? sourceYieldedResponse : undefined;
+          return segmentIndex === yieldedResponseSegmentIndex
+            ? paperclipRunnerFinalResponse(parsed, yieldedOptions)
+            : undefined;
+        }
+        if (sourceHasPresentationComment) return undefined;
+        // A steering anchor may split acceptance from its terminal. Keep the
+        // whole-run proof and render its answer exactly once.
+        if (sourceAcceptedResponseWake) {
+          return lastSegment
+            ? paperclipRunnerFinalResponse(parsedSource, { runId: source.id, agentName: meta?.agentName })
+            : undefined;
+        }
+        return paperclipRunnerFinalResponse(parsed, {
+          runId: source.id,
+          agentName: meta?.agentName,
+          fallbackSummary: lastSegment ? acceptedSummary : undefined,
+          allowFallback: sourceAllowSummaryFallback,
+        });
+      };
       for (const [segmentIndex, projected] of projectedSegments.entries()) {
         const { segment, parsed } = projected;
         if (segment.entries.length === 0) continue;
-        const finalResponse =
-          sourceIsPaperclipRunner && sourceYielded
-            ? segmentIndex === lastPopulatedSegmentIndex
-              ? sourceYieldedResponse
-              : undefined
-            : sourceIsPaperclipRunner &&
-          !sourceHasPresentationComment
-            ? sourceAcceptedResponseWake
-              ? // A steering anchor may split acceptance from its terminal.
-                // Keep the whole-run proof and render its answer exactly once.
-                segmentIndex === lastPopulatedSegmentIndex
-                ? paperclipRunnerFinalResponse(parsedSource, {
-                    runId: source.id,
-                    agentName: meta?.agentName,
-                  })
-                : undefined
-              : paperclipRunnerFinalResponse(parsed, {
-                  runId: source.id,
-                  agentName: meta?.agentName,
-                  fallbackSummary:
-                    segmentIndex === lastPopulatedSegmentIndex
-                      ? acceptedSummary
-                      : undefined,
-                  allowFallback: sourceAllowSummaryFallback,
-                })
-            : undefined;
+        const finalResponse = settledSegmentFinalResponse(segmentIndex, parsed);
         const runHealth = {
           failures: projectedSegments[segmentIndex]?.mcpStartupFailures ?? [],
           rest: partitionRunHealthItems(timelineItemsBySegment[segmentIndex] ?? []).rest,
@@ -2451,7 +2469,7 @@ export function TaskChatThread(props: TaskChatThreadProps) {
     ? runs.find((run) => run.id === tailRunId)
     : undefined;
   const paperclipRunnerTail = isNativePaperclipRunnerRun(tailRunSource);
-  const suppressPaperclipRunnerTailFinal = Boolean(
+  const paperclipRunnerTailAwaitingContinuation = Boolean(
     paperclipRunnerTail &&
     (acceptedSemanticResultDisposition(
       tailRunId ? linkedRunMetaById.get(tailRunId)?.resultJson : null,
@@ -3401,8 +3419,8 @@ export function TaskChatThread(props: TaskChatThreadProps) {
                                       startedAtMs={tailStartedAtMs}
                                       finishedAtMs={tailFinishedAtMs}
                                       activityUnavailable={tailActivityUnavailable}
-                                      suppressFinal={
-                                        suppressPaperclipRunnerTailFinal
+                                      awaitingContinuation={
+                                        paperclipRunnerTailAwaitingContinuation
                                       }
                                       waitSummary={acceptedSemanticResultSummary(
                                         tailRunId ? linkedRunMetaById.get(tailRunId)?.resultJson : null,

ui/src/components/task-chat/TaskChatRunnerTurn.test.tsx

@@ -40,7 +40,7 @@ describe("TaskChatRunnerTurn", () => {
       item: TaskChatRuntimeRequestItem,
       decision: TaskChatRuntimeRequestDecision,
     ) => void,
-    suppressFinal = false,
+    awaitingContinuation = false,
     continuedAfterSteering = false,
     execution?: ExecutionProjection,
     preparationLabel?: string,
@@ -58,7 +58,7 @@ describe("TaskChatRunnerTurn", () => {
               execution={execution}
               preparationLabel={preparationLabel}
               startedAtMs={Date.now() - 2_000}
-              suppressFinal={suppressFinal}
+              awaitingContinuation={awaitingContinuation}
               continuedAfterSteering={continuedAfterSteering}
               onRuntimeRequestDecision={onRuntimeRequestDecision}
             />

ui/src/components/task-chat/TaskChatRunnerTurn.tsx

@@ -158,7 +158,7 @@ export function TaskChatRunnerTurn({
   finishedAtMs,
   activityUnavailable = false,
   allowSummaryFallback = true,
-  suppressFinal = false,
+  awaitingContinuation = false,
   waitSummary = null,
   continuedAfterSteering = false,
   showHeader = true,
@@ -183,7 +183,7 @@ export function TaskChatRunnerTurn({
    * provider final that only restates the wait is not presented as a reply.
    * Prose the agent wrote for the user stays visible.
    */
-  suppressFinal?: boolean;
+  awaitingContinuation?: boolean;
   /** The accepted yielded result's wait summary, when known. */
   waitSummary?: string | null;
   /** The visible tail resumes the same native run after an accepted steer. */
@@ -204,7 +204,7 @@ export function TaskChatRunnerTurn({
       item.surface === "run_result" &&
       item.disposition === "yielded",
   );
-  const observedFinal = paperclipRunnerFinalResponse(turnItems, suppressFinal
+  const observedFinal = paperclipRunnerFinalResponse(turnItems, awaitingContinuation
     ? { allowFallback: false, yielded: true, waitSummary }
     : { allowFallback: terminal && allowSummaryFallback });
   const observedProviderText = Boolean(
@@ -229,7 +229,7 @@ export function TaskChatRunnerTurn({
   // A provider final can arrive before the accepted yielded result. Clear any
   // replay latch once the control plane establishes that this turn is waiting
   // for continuation; only an authored (non-wait) final is re-latched below.
-  if (yielded || suppressFinal) finalRef.current = { runId };
+  if (yielded || awaitingContinuation) finalRef.current = { runId };
   if (
     observedFinal &&
     (!finalRef.current.item ||