fix(rectification): ask remaining split lines one card at a time (BUG-661~663)

Dated-pool empty now yields existence cards per remaining layer, leftover-candidate copy, and an optional D9/D10 tie-break on the range card. Skill 10.0.25.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/components/rectification-agentic-chat.tsx

@@ -1368,6 +1368,35 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
     }
   }, [acceptingCandidateId, beginLiveRun, busy, candidateResult, caseId, loadCaseSnapshot, onCompleted, onSaved, readonly, send, sessionId, setPending]);
 
+  const requestTieBreak = useCallback(async () => {
+    if (!candidateResult || acceptingCandidateId || busy || readonly) return;
+    if (!candidateResult.rangeDelivery?.tie_break_available) return;
+    setError("");
+    setPending(true);
+    try {
+      const response = await fetch(
+        `/api/rectification/cases/${encodeURIComponent(caseId)}/tie-break`,
+        {
+          method: "POST",
+          headers: { "content-type": "application/json" },
+          body: JSON.stringify({
+            sessionId,
+            requestId: globalThis.crypto.randomUUID(),
+          }),
+        },
+      );
+      const payload = await response.json().catch(() => null);
+      if (!response.ok || payload?.ok !== true) {
+        throw new Error(payload?.error || payload?.message || "暂时无法开始参考题");
+      }
+      await loadCaseSnapshot();
+    } catch (caught) {
+      setError(caught instanceof Error ? caught.message : "暂时无法开始参考题");
+    } finally {
+      setPending(false);
+    }
+  }, [acceptingCandidateId, busy, candidateResult, caseId, loadCaseSnapshot, readonly, sessionId, setPending]);
+
   async function copyMessage(message: RenderMessage) {
     try {
       await navigator.clipboard.writeText(copyTextForMessage(message.text, message.question));
@@ -1795,6 +1824,7 @@ export function RectificationAgenticChat(props: RectificationAgenticChatProps) {
                       acceptingCandidateId={acceptingCandidateId}
                       readonly={readonly || regeneratingMessageKey !== null || (busy && !acceptingCandidateId)}
                       onAccept={(candidateId) => void acceptCandidate(candidateId)}
+                      onTieBreak={() => void requestTieBreak()}
                     />
                     {verifiedIdleCopy && (
                       <p className="rectification-pending-note" role="status">

frontend/src/components/rectification-range-delivery.tsx

@@ -18,11 +18,13 @@ export function RectificationRangeDelivery({
   acceptingCandidateId,
   readonly,
   onAccept,
+  onTieBreak,
 }: Readonly<{
   result: RectificationCandidateResult;
   acceptingCandidateId: string | null;
   readonly: boolean;
   onAccept: (candidateId: string) => void;
+  onTieBreak?: () => void;
 }>) {
   const delivery: RangeDeliveryProjection | null = result.rangeDelivery;
   const range = delivery?.range ?? result.credibleRange;
@@ -47,6 +49,16 @@ export function RectificationRangeDelivery({
       {delivery?.narrow_hint ? (
         <p className="rectification-range-delivery__narrow">{delivery.narrow_hint}</p>
       ) : null}
+      {delivery?.tie_break_available && onTieBreak && !readonly ? (
+        <button
+          type="button"
+          className="rectification-range-delivery__tie-break"
+          disabled={busy}
+          onClick={onTieBreak}
+        >
+          {RECTIFICATION_USER_COPY.rangeDeliveryTieBreakEntry}
+        </button>
+      ) : null}
       {sharedTraits.length > 0 ? (
         <ul className="rectification-range-delivery__shared">
           {sharedTraits.map((line) => (