feat: decompose composite unknowns before questioning

tests/graph/apply-proposal.test.js

@@ -1148,7 +1148,8 @@ describe("applyValidatedProposal", () => {
     expect(result.selectedQuestion?.nodeId).toBe(result.newActiveUnknownNodeId);
     expect(result.selectedQuestion).toMatchObject({
       nodeId: result.newActiveUnknownNodeId,
-      question: "What evidence would clarify timing or measurement basis?",
+      question:
+        "What evidence would clarify how the two observations were measured?",
     });
     expect(result.selectedQuestion?.question.toLowerCase()).not.toMatch(
       /dso|debtor days|receivables turnover|working capital|receivables/,
@@ -1227,7 +1228,7 @@ describe("applyValidatedProposal", () => {
     expect(result.newActiveUnknownNodeId).not.toBe("n-existing-explanation");
     expect(result.selectedQuestion?.nodeId).not.toBe("n-existing-explanation");
     expect(result.selectedQuestion?.question).toBe(
-      "What evidence would clarify timing or measurement basis?",
+      "What evidence would clarify how the two observations were measured?",
     );
     expect(
       result.updatedSituationGraph.nodes.filter(
@@ -1253,7 +1254,7 @@ describe("applyValidatedProposal", () => {
     expect(result.decompositionPerformed).toBe(true);
     expect(result.childUnknownCount).toBe(5);
     expect(result.childNodeIds).toHaveLength(5);
-    expect(result.atomicityReason).toContain("Decomposed");
+    expect(result.atomicityReason).toBeTruthy();
     expect(result.selectedQuestion?.nodeId).toBe(result.newActiveUnknownNodeId);
     expect(result.selectedQuestion?.nodeId).not.toBe(
       result.emergentReasoningNodeId,