fix(reasoning): preserve investigation ownership across selection and question rejection

tests/graph/orchestrator.test.js

@@ -1,7 +1,9 @@
 import { beforeEach, describe, expect, it, vi } from "vitest";
 import { applyValidatedProposal } from "@/lib/graph/apply-proposal.js";
+import { determineGraphBackedQuestion } from "@/lib/graph/apply-proposal.js";
 import { validateGraphReferences } from "@/lib/graph/utils.js";
 import { makeGraph, makeNode } from "@/lib/graph/schema.js";
+import liveProductLaunchStartResponse from "@/tests/fixtures/live-product-launch-start-response.json";
 
 const mockAnalyseScenario = vi.fn();
 const MOCK_CONFIG = { OLLAMA_MODEL: "configured" };
@@ -588,6 +590,46 @@ describe("lib/graph/orchestrator startCase", () => {
     );
   });
 
+  it("retains ownership when the strongest target's formulated question is rejected", () => {
+    const situationGraph = structuredClone(
+      liveProductLaunchStartResponse.situationGraph,
+    );
+
+    const result = determineGraphBackedQuestion({ situationGraph });
+
+    expect(result.success).toBe(true);
+    expect(result.deterministicSelection?.nodeId ?? null).toBe("ntpt9ki");
+    expect(result.updatedSituationGraph.activeUnknownNodeId).toBe("ntpt9ki");
+    expect(result.selectedQuestion).toBeNull();
+    expect(result.noQuestionReason).toBe(
+      "The selected investigation target remains active, but its current graph-backed question formulation was rejected as too complex.",
+    );
+    expect(result.selectedChildUnknown).toBe("ntpt9ki");
+    expect(result.selectedUnknownAfter).toBe("ntpt9ki");
+    expect(result.selectedQuestion?.nodeId ?? null).toBe(null);
+  });
+
+  it("replays the captured live product-launch start graph through deterministic graph-backed question selection", () => {
+    const situationGraph = liveProductLaunchStartResponse.situationGraph;
+
+    const result = determineGraphBackedQuestion({ situationGraph });
+
+    expect(result.success).toBe(true);
+    expect(result.updatedSituationGraph.activeUnknownNodeId).toBe("ntpt9ki");
+    expect(result.deterministicSelection?.nodeId ?? null).toBe("ntpt9ki");
+    expect(result.answerabilityAssessment?.independentlyAnswerable).toBe(false);
+    expect(result.answerabilityAssessment?.decompositionRequired).toBe(true);
+    expect(result.decompositionAttempted).toBe(true);
+    expect(result.decompositionPerformed).toBe(false);
+    expect(result.selectedChildUnknown).toBe("ntpt9ki");
+    expect(result.selectedUnknownAfter).toBe("ntpt9ki");
+    expect(result.selectedQuestion).toBeNull();
+    expect(result.noQuestionReason).toBe(
+      "The selected investigation target remains active, but its current graph-backed question formulation was rejected as too complex.",
+    );
+    expect(result.deterministicSelection?.nodeId).not.toBe("nxmeiab");
+  });
+
   it("includes compatibility diagnostics when provided by analysis", async () => {
     mockAnalyseScenario.mockResolvedValue(
       makeAnalysisResult({