fix(confidence-engine): workspace control cleanup — rename close button, remove 'Back to open questions' from navigation

components/reasoning-workspace.jsx

@@ -393,17 +393,10 @@ function FocusedQuestionBody({
 
 // ── Persistent navigation controls (overlay-level, outside content grid) ──
 
-function FocusedWorkspaceNavigation({ nodeId, doneForNow, onBackToOpenQuestions, isDoneForNowActive }) {
+function FocusedWorkspaceNavigation({ nodeId, doneForNow, isDoneForNowActive }) {
   const canDoneForNow = Boolean(isDoneForNowActive);
   return (
-    <div className="mt-6 flex items-center justify-between gap-4 border-t border-gray-200 pt-5">
-      <button
-        onClick={(e) => { e.stopPropagation(); onBackToOpenQuestions?.(); }}
-        style={{ cursor: "pointer" }}
-        className="text-sm text-gray-400 underline hover:text-gray-600 transition whitespace-nowrap"
-      >
-        Back to open questions
-      </button>
+    <div className="mt-6 flex items-center justify-end border-t border-gray-200 pt-5">
       <button
         onClick={(e) => { e.stopPropagation(); doneForNow?.(); }}
         style={{ cursor: canDoneForNow ? "pointer" : "not-allowed" }}
@@ -2131,12 +2124,12 @@ export default function ReasoningWorkspace({
                 <button
                   onClick={(e) => { e.stopPropagation(); setFocusedAnswer(""); setFocusedPresentationItemId(null); setIsFocusedWorkspaceOpen(false); }}
                   style={{ cursor: "pointer" }}
-                  aria-label="Close investigation"
-                  title="Close investigation"
+                  aria-label="Close workspace"
+                  title="Close workspace"
                   className="absolute right-4 top-3 z-20 flex items-center gap-2 rounded-lg border border-gray-300 bg-white/90 px-4 py-2 text-sm font-medium text-gray-600 shadow-sm transition hover:bg-gray-50"
                 >
                   <svg width="14" height="14" viewBox="0 0 14 14" fill="none" stroke="currentColor" strokeWidth="2" strokeLinecap="round"><path d="M1 1l12 12M13 1L1 13"/></svg>
-                  Close investigation
+                  Close workspace
                 </button>
 
                 {/* Scrollable workspace body */}
@@ -2182,10 +2175,6 @@ export default function ReasoningWorkspace({
                             setFocusedPresentationItemId(null);
                           }}
                           isDoneForNowActive={Boolean(getFocusedInvestigation()?.question?.trim())}
-                          onBackToOpenQuestions={() => {
-                            setFocusedAnswer("");
-                            setFocusedPresentationItemId(null);
-                          }}
                         />
                       )}
                     </>