Polish Today dashboard loading, errors, and layout (Phase 4).

Add section error boundaries, retry banner with stale-while-revalidate, shared skeletons, responsive action layout, and org-switch refetching.

Co-authored-by: Cursor <cursoragent@cursor.com>

frontend/src/lib/hooks/useTodaySummary.ts

@@ -9,17 +9,19 @@ import type { ApiError } from '@/types/api';
 interface UseTodaySummaryResult {
   data: TodaySummaryData | null;
   loading: boolean;
+  isInitialLoad: boolean;
   error: ApiError | null;
   reload: () => Promise<void>;
 }
 
-export function useTodaySummary(enabled = true): UseTodaySummaryResult {
+export function useTodaySummary(organizationId?: string | null): UseTodaySummaryResult {
+  const enabled = Boolean(organizationId);
   const [data, setData] = useState<TodaySummaryData | null>(null);
   const [loading, setLoading] = useState(enabled);
   const [error, setError] = useState<ApiError | null>(null);
 
   const reload = useCallback(async () => {
-    if (!enabled) {
+    if (!organizationId) {
       setData(null);
       setLoading(false);
       setError(null);
@@ -34,16 +36,28 @@ export function useTodaySummary(enabled = true): UseTodaySummaryResult {
       const response = await todayApi.summary(range);
       setData(response.data);
     } catch (err) {
-      setData(null);
       setError(err as ApiError);
     } finally {
       setLoading(false);
     }
-  }, [enabled]);
+  }, [organizationId]);
 
   useEffect(() => {
+    setData(null);
+    setError(null);
+    if (!organizationId) {
+      setLoading(false);
+      return;
+    }
+    setLoading(true);
     void reload();
-  }, [reload]);
+  }, [organizationId, reload]);
 
-  return { data, loading, error, reload };
+  return {
+    data,
+    loading,
+    isInitialLoad: loading && !data,
+    error,
+    reload,
+  };
 }