refactor: dedupe split-view render, strengthen persistence test

- Extract ConsoleArea helper to eliminate ~60 lines of duplicated layout
  toggle + grid rendering shared between currentLane and !currentLane branches
- Fix persistence test to validate the component's actual write path instead
  of manually re-seeding localStorage (proves writeSplitViewState is called)
- Remove orphaned grid/pane code left by incomplete merge

client/src/pages/Workspace.tsx

@@ -54,6 +54,97 @@ import type { SplitViewState, SplitLayout } from "../lib/splitViewStorage";
 
 // ── Page ──────────────────────────────────────────────────────────────
 
+function ConsoleArea({
+  lanes,
+  selectedLaneId,
+  splitView,
+  setLayout,
+  setPaneLaneId,
+  binaryStatus,
+  cwdSuggestions,
+  activeRuns,
+  wsConnected,
+  defaultCwd,
+  onHasActiveRunChange,
+  onLaneCreated,
+  onLaneIdChange,
+}: {
+  lanes: Lane[];
+  selectedLaneId: number | null;
+  splitView: SplitViewState;
+  setLayout: (layout: SplitLayout) => void;
+  setPaneLaneId: (index: number, id: number) => void;
+  binaryStatus: { found: boolean; path: string | null } | null;
+  cwdSuggestions: CwdSuggestion[];
+  activeRuns: RunListResponse | null;
+  wsConnected: boolean;
+  defaultCwd: string;
+  onHasActiveRunChange: (val: boolean) => void;
+  onLaneCreated: (lane: Lane) => void;
+  onLaneIdChange: (id: number | null) => void;
+}) {
+  const { t: tLanes } = useTranslation("lanes");
+
+  return (
+    <>
+      <div className="flex items-center gap-1.5">
+        {([1, 2, 4] as const).map((n) => (
+          <button
+            key={n}
+            type="button"
+            aria-pressed={splitView.layout === n}
+            onClick={() => setLayout(n)}
+            className={`rounded border px-2 py-1 text-xs ${
+              splitView.layout === n
+                ? "border-accent bg-accent/15 text-accent"
+                : "border-border text-fg-secondary hover:border-border-light"
+            }`}
+          >
+            {tLanes("splitView.paneCount", { count: n })}
+          </button>
+        ))}
+      </div>
+      {splitView.layout === 1 ? (
+        <LaneConsolePane
+          lanes={lanes}
+          laneId={selectedLaneId}
+          showLaneSelector={false}
+          onLaneIdChange={onLaneIdChange}
+          onLaneCreated={onLaneCreated}
+          binaryStatus={binaryStatus}
+          cwdSuggestions={cwdSuggestions}
+          activeRuns={activeRuns}
+          wsConnected={wsConnected}
+          defaultCwd={defaultCwd}
+          onHasActiveRunChange={onHasActiveRunChange}
+        />
+      ) : (
+        <div
+          className={`grid flex-1 min-h-0 gap-3 ${
+            splitView.layout === 2 ? "grid-cols-2" : "grid-cols-2 grid-rows-2"
+          }`}
+        >
+          {splitView.paneLaneIds.map((id, i) => (
+            <LaneConsolePane
+              key={i}
+              lanes={lanes}
+              laneId={id}
+              showLaneSelector
+              onLaneIdChange={(newId) => setPaneLaneId(i, newId)}
+              onLaneCreated={onLaneCreated}
+              binaryStatus={binaryStatus}
+              cwdSuggestions={cwdSuggestions}
+              activeRuns={activeRuns}
+              wsConnected={wsConnected}
+              defaultCwd={defaultCwd}
+            />
+          ))}
+        </div>
+      )}
+    </>
+  );
+}
+
 export function Workspace() {
   const { t: tLanes } = useTranslation("lanes");
   const wsConnected = useSyncExternalStore(eventBus.onConnection, () => eventBus.connected);
@@ -552,132 +643,46 @@ export function Workspace() {
               </div>
             )}
           <div className="flex min-h-0 flex-col gap-2 border-t border-border pt-3">
-            <div className="flex items-center gap-1.5">
+            <ConsoleArea
-              {([1, 2, 4] as const).map((n) => (
-                <button
-                  key={n}
-                  type="button"
-                  aria-pressed={splitView.layout === n}
-                  onClick={() => setLayout(n)}
-                  className={`rounded border px-2 py-1 text-xs ${
-                    splitView.layout === n
-                      ? "border-accent bg-accent/15 text-accent"
-                      : "border-border text-fg-secondary hover:border-border-light"
-                  }`}
-                >
-                  {tLanes("splitView.paneCount", { count: n })}
-                </button>
-              ))}
-            </div>
-            {splitView.layout === 1 ? (
-              <LaneConsolePane
-                lanes={lanes}
-                laneId={selectedLaneId}
-                showLaneSelector={false}
-                onLaneIdChange={(id) => setSelectedLaneId(id)}
-                onLaneCreated={(lane) =>
-                  setLanes((prev) => (prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]))
-                }
-                binaryStatus={binaryStatus}
-                cwdSuggestions={cwdSuggestions}
-                activeRuns={activeRuns}
-                wsConnected={wsConnected}
-                defaultCwd={defaultCwd}
-                onHasActiveRunChange={setPaneHasActiveRun}
-              />
-            ) : (
-              <div
-                className={`grid flex-1 min-h-0 gap-3 ${
-                  splitView.layout === 2 ? "grid-cols-2" : "grid-cols-2 grid-rows-2"
-                }`}
-              >
-                {splitView.paneLaneIds.map((id, i) => (
-                  <LaneConsolePane
-                    key={i}
-                    lanes={lanes}
-                    laneId={id}
-                    showLaneSelector
-                    onLaneIdChange={(newId) => setPaneLaneId(i, newId)}
-                    onLaneCreated={(lane) =>
-                      setLanes((prev) =>
-                        prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]
-                      )
-                    }
-                    binaryStatus={binaryStatus}
-                    cwdSuggestions={cwdSuggestions}
-                    activeRuns={activeRuns}
-                    wsConnected={wsConnected}
-                    defaultCwd={defaultCwd}
-                  />
-                ))}
-              </div>
-            )}
-          </div>
-        </section>
-      )}
-
-      {!currentLane && (
-        <div className="flex min-h-0 flex-col gap-2">
-          <div className="flex items-center gap-1.5">
-            {([1, 2, 4] as const).map((n) => (
-              <button
-                key={n}
-                type="button"
-                aria-pressed={splitView.layout === n}
-                onClick={() => setLayout(n)}
-                className={`rounded border px-2 py-1 text-xs ${
-                  splitView.layout === n
-                    ? "border-accent bg-accent/15 text-accent"
-                    : "border-border text-fg-secondary hover:border-border-light"
-                }`}
-              >
-                {tLanes("splitView.paneCount", { count: n })}
-              </button>
-            ))}
-          </div>
-          {splitView.layout === 1 ? (
-            <LaneConsolePane
               lanes={lanes}
-              laneId={selectedLaneId}
+              selectedLaneId={selectedLaneId}
-              showLaneSelector={false}
+              splitView={splitView}
-              onLaneIdChange={(id) => setSelectedLaneId(id)}
+              setLayout={setLayout}
-              onLaneCreated={(lane) =>
+              setPaneLaneId={setPaneLaneId}
-                setLanes((prev) => (prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]))
-              }
               binaryStatus={binaryStatus}
               cwdSuggestions={cwdSuggestions}
               activeRuns={activeRuns}
               wsConnected={wsConnected}
               defaultCwd={defaultCwd}
               onHasActiveRunChange={setPaneHasActiveRun}
+              onLaneCreated={(lane) =>
+                setLanes((prev) => (prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]))
+              }
+              onLaneIdChange={setSelectedLaneId}
             />
-          ) : (
+          </div>
-            <div
+        </section>
-              className={`grid flex-1 min-h-0 gap-3 ${
+      )}
-                splitView.layout === 2 ? "grid-cols-2" : "grid-cols-2 grid-rows-2"
+
-              }`}
+      {!currentLane && (
-            >
+        <div className="flex min-h-0 flex-col gap-2">
-              {splitView.paneLaneIds.map((id, i) => (
+          <ConsoleArea
-                <LaneConsolePane
+            lanes={lanes}
-                  key={i}
+            selectedLaneId={selectedLaneId}
-                  lanes={lanes}
+            splitView={splitView}
-                  laneId={id}
+            setLayout={setLayout}
-                  showLaneSelector
+            setPaneLaneId={setPaneLaneId}
-                  onLaneIdChange={(newId) => setPaneLaneId(i, newId)}
+            binaryStatus={binaryStatus}
-                  onLaneCreated={(lane) =>
+            cwdSuggestions={cwdSuggestions}
-                    setLanes((prev) =>
+            activeRuns={activeRuns}
-                      prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]
+            wsConnected={wsConnected}
-                    )
+            defaultCwd={defaultCwd}
-                  }
+            onHasActiveRunChange={setPaneHasActiveRun}
-                  binaryStatus={binaryStatus}
+            onLaneCreated={(lane) =>
-                  cwdSuggestions={cwdSuggestions}
+              setLanes((prev) => (prev.some((l) => l.id === lane.id) ? prev : [...prev, lane]))
-                  activeRuns={activeRuns}
+            }
-                  wsConnected={wsConnected}
+            onLaneIdChange={setSelectedLaneId}
-                  defaultCwd={defaultCwd}
+          />
-                />
-              ))}
-            </div>
-          )}
         </div>
       )}
 

client/src/pages/__tests__/Workspace.test.tsx

@@ -671,12 +671,6 @@ describe("split terminal view", () => {
     await settle();
     unmount();
 
-    localStorage.clear();
-    localStorage.setItem(
-      "ccam.workspace.splitView",
-      JSON.stringify({ layout: 2, paneLaneIds: [null, lanesToReturn[1]!.id] })
-    );
-
     await renderWorkspace();
     const persistedSelects = screen.getAllByTestId("pane-lane-select");
     expect(persistedSelects).toHaveLength(2);