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>
       )}