test(ui): make inferred questions originate branches

components/reasoning-workspace.jsx

@@ -362,17 +362,28 @@ function BranchNotebookContent({
 
   return (
     <div className="space-y-6">
-      {/* Why this branch exists */}
+      {/* Why this branch exists — origin question is primary */}
       {branchContext && (
         <div className="rounded-lg border border-blue-200/60 bg-blue-50/40 px-5 py-4">
           <h2 className="mb-1 text-[11px] font-semibold tracking-widest uppercase text-gray-500">
-            Current branch
+            Investigating
           </h2>
-          <p className="text-base font-medium leading-tight text-gray-900">{branchContext.label}</p>
-          {branchContext.origin && (
-            <p className="mt-2 text-sm leading-relaxed text-gray-600">
-              Trying to understand: {branchContext.origin}
-            </p>
+          {branchContext.originQuestion ? (
+            <>
+              <p className="text-base leading-relaxed text-gray-900">{branchContext.originQuestion.text}</p>
+              {branchContext.label && branchContext.originQuestion.text !== branchContext.label && (
+                <p className="mt-2 text-xs text-gray-500/70">Branch: {branchContext.label}</p>
+              )}
+            </>
+          ) : branchContext.origin ? (
+            <>
+              <p className="text-base font-medium leading-tight text-gray-900">{branchContext.label}</p>
+              <p className="mt-2 text-sm leading-relaxed text-gray-600">
+                Trying to understand: {branchContext.origin}
+              </p>
+            </>
+          ) : (
+            <p className="text-base font-medium leading-tight text-gray-900">{branchContext.label}</p>
           )}
         </div>
       )}

components/scenario-form.jsx

@@ -237,8 +237,8 @@ export function derivePrimarySurface(result, status, showExperimentView, scenari
 
   const valid = hasValidInvestigationContext(result, status, scenario);
 
-  // RTO.28A: show branch-selection surface when investigation exists but no branch is active
-  if (showExperimentView && valid && !activeBranchId) return "BRANCH_SELECTION";
+  // RTO.28B: show question-selection surface when investigation exists but no question/branch is active
+  if (showExperimentView && valid && !activeBranchId) return "QUESTION_SELECTION";
 
   if (showExperimentView && valid) return "EXPERIMENT_NOTEBOOK";
   if (!showExperimentView && valid) return "NORMAL_WORKSPACE";
@@ -283,6 +283,15 @@ export default function ScenarioForm() {
   // Use fixture branches as the authoritative source when available
   const BRANCHES = useMemo(() => branchScoped.getBranches(), [branchScoped]);
 
+  // Track the originating question for provenance
+  const [originQuestion, setOriginQuestion] = useState(null);
+
+  // Extract inferred questions from the fixture (flat list for post-Analyse surface)
+  const inferredQuestions = useMemo(() => {
+    if (!branchScoped || typeof branchScoped.getAllInferredQuestions !== 'function') return [];
+    return branchScoped.getAllInferredQuestions();
+  }, [branchScoped]);
+
   // Simulate a late semantic result arriving on Branch A ~2s after a graph loads
   useEffect(() => {
     if (status !== "success" && status !== "error") return;
@@ -538,7 +547,7 @@ export default function ScenarioForm() {
         <>
           <PulseStyle />
           {!activeBranchId ? (
-            /* RTO.28A: no active branch — show branch-selection surface */
+            /* RTO.28B: inferred questions surface — user chooses what to investigate */
             <div className="max-w-xl mx-auto space-y-6">
               <div className="space-y-4">
                 {/* Situation remains visible */}
@@ -552,25 +561,30 @@ export default function ScenarioForm() {
                 )}
               </div>
 
-              {/* Branch selection */}
+              {/* Inferred questions — user chooses what to investigate */}
               <div className="space-y-4">
-                <h2 className="text-xs font-medium text-gray-700">Choose a branch to continue</h2>
-                <p className="text-sm text-gray-500">These are the current lines of inquiry. Pick whichever you want to work on.</p>
+                <h2 className="text-xs font-medium text-gray-700">Questions to explore</h2>
+                <p className="text-sm text-gray-500">Click a question to start investigating. A branch will be created for your choice.</p>
 
-                {BRANCHES.map((branch) => (
+                {inferredQuestions.map((q) => (
                   <button
-                    key={branch.id}
-                    onClick={() => setActiveBranchId(branch.id)}
+                    key={q.id}
+                    onClick={() => {
+                      const targetBranch = BRANCHES.find(b => b.id === q.branchId);
+                      if (targetBranch) {
+                        setActiveBranchId(targetBranch.id);
+                        setOriginQuestion({ id: q.id, text: q.text });
+                      }
+                    }}
                     className="w-full text-left rounded-lg border border-gray-200 bg-white px-5 py-4 transition hover:border-gray-300 hover:bg-gray-50"
                   >
-                    <span className="block font-medium text-sm text-gray-900">{branch.label}</span>
-                    {branch.origin && (
-                      <span className="block mt-1 text-xs leading-relaxed text-gray-500/80">
-                        {branch.origin}
-                      </span>
-                    )}
+                    <span className="block text-sm leading-relaxed text-gray-900">{q.text}</span>
                   </button>
                 ))}
+
+                {inferredQuestions.length === 0 && (
+                  <p className="text-sm text-gray-400">No questions available yet.</p>
+                )}
               </div>
             </div>
           ) : (
@@ -592,7 +606,7 @@ export default function ScenarioForm() {
                       setAnswer={() => {}}
                       onAnswerSubmit={async (e) => e.preventDefault()}
                       lastSubmittedAnswer=""
-                      branchContext={branchContext}
+                      branchContext={{ ...branchContext, originQuestion: originQuestion }}
                       experimentalBranches={BRANCHES.length > 0 ? BRANCHES : undefined}
                       branchLocalQuestions={experimentalBranchQuestions.length > 0 ? experimentalBranchQuestions : undefined}
                       branchLocalContributions={experimentalBranchContributions.length > 0 ? experimentalBranchContributions : undefined}

lib/fixtures/rto26b-branch-scoped.mjs

@@ -190,6 +190,21 @@ export function useBranchScopedFixture() {
       return Object.values(BRANCH_META).map(m => ({ ...m }));
     },
 
+    /** Return all inferred questions across branches (flat list for post-Analyse surface). */
+    getAllInferredQuestions() {
+      const qA1 = this._qA1;
+      const qA2 = this._qA2;
+      const qB1 = this._qB1;
+      const qB2 = this._qB2;
+      if (!qA1 || !qA2 || !qB1 || !qB2) return [];
+      return [
+        { id: qA1.id, text: qA1.text, branchId: "branch-competitor-development" },
+        { id: qA2.id, text: qA2.text, branchId: "branch-competitor-development" },
+        { id: qB1.id, text: qB1.text, branchId: "branch-customer-demand" },
+        { id: qB2.id, text: qB2.text, branchId: "branch-customer-demand" },
+      ];
+    },
+
     /** Return all records (for verification / debugging). */
     getAllRecords() {
       return allRecords;