chore: estructura inicial del MVP

Backend (Express + MariaDB) y frontend (React + Vite, identidad Fluent/Windows) con el
nucleo funcional: seguridad, organizacion, proyectos, actividades, subtareas, dependencias,
dashboard, calendario, gantt, comentarios, adjuntos, notificaciones in-app y catalogos.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/hooks/useAsync.js

@@ -0,0 +1,40 @@
+import { useCallback, useEffect, useState } from 'react';
+import { useUi } from '../context/ui-context.jsx';
+
+// Abstrae el patron repetido loading/try-catch/error para llamadas a la API.
+export function useAsync(fn, deps = []) {
+  const [data, setData] = useState(null);
+  const [loading, setLoading] = useState(true);
+  const [error, setError] = useState(null);
+
+  const reload = useCallback(async () => {
+    setLoading(true);
+    setError(null);
+    try {
+      const result = await fn();
+      setData(result);
+    } catch (err) {
+      setError(err.message);
+    } finally {
+      setLoading(false);
+    }
+  // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, deps);
+
+  useEffect(() => { reload(); }, [reload]);
+
+  return { data, loading, error, reload, setData };
+}
+
+// Ejecuta una accion mostrando error via ContentDialog si falla.
+export function useAction() {
+  const { openDialog, t } = useUi();
+  return useCallback(async (fn) => {
+    try {
+      return await fn();
+    } catch (err) {
+      openDialog({ tone: 'error', title: t('common_error'), message: err.message });
+      throw err;
+    }
+  }, [openDialog, t]);
+}