fix(export): optimizar lógica de descarga y manejo de estado en componentes de exportación

Se eliminan condiciones innecesarias en el componente ExportDropdown y se mejora la lógica de selección de publicaciones en DashboardPage y GroupResultsPage. Se asegura que la desactivación de botones se base únicamente en el estado de carga y cooldown, mejorando la experiencia del usuario al evitar mensajes de notificación redundantes.

frontend/src/components/dashboard/ExportDropdown.jsx

@@ -26,9 +26,6 @@ export function ExportDropdown({
   const isBusy = Boolean(exportingFormat);
   const hasSelection = selectedCount > 0;
 
-  const nothingToDownload =
-    isAuthenticated && !hasSelection && newPublicationsCount === 0;
-
   function handleDownload() {
     const { format, profile } = resolveExportFromDestination(exportDestination);
     onExport(format, profile);
@@ -62,7 +59,7 @@ export function ExportDropdown({
       <button
         type="button"
         onClick={handleDownload}
-        disabled={disabled || isBusy || nothingToDownload}
+        disabled={disabled || isBusy}
         className="inline-flex w-full items-center justify-center gap-2 rounded-lg border border-surface-border-strong bg-surface-primary px-[18px] py-2.5 text-sm font-medium text-ink-primary transition-colors enabled:hover:bg-surface-secondary disabled:cursor-not-allowed disabled:opacity-70 sm:w-auto"
       >
         {isBusy ? (

frontend/src/pages/DashboardPage.jsx

@@ -245,15 +245,9 @@ export function DashboardPage() {
         // Manual selection takes priority
         ids = Array.from(selectedIds);
       } else if (isAuthenticated) {
-        // Authenticated → only download publications not yet downloaded by me
+        // Prefer undownloaded; if none left, allow re-downloading the full profile
-        ids = newPublicationIds;
+        ids =
-        if (ids.length === 0) {
+          newPublicationIds.length > 0 ? newPublicationIds : undefined;
-          toast.info("No hay publicaciones nuevas", {
-            id: EXPORT_TOAST_ID,
-            description: "Ya has descargado todas las publicaciones de este investigador.",
-          });
-          return;
-        }
       } else {
         // Anonymous → download everything
         ids = undefined;
@@ -282,12 +276,19 @@ export function DashboardPage() {
       if (selectedIds.size > 0) {
         scope = `${selectedIds.size} publicación${selectedIds.size === 1 ? "" : "es"} seleccionada${selectedIds.size === 1 ? "" : "s"}`;
       } else if (isAuthenticated) {
-        scope = `${newPublicationIds.length} publicación${newPublicationIds.length === 1 ? "" : "es"} nueva${newPublicationIds.length === 1 ? "" : "s"}`;
+        scope =
+          newPublicationIds.length > 0
+            ? `${newPublicationIds.length} publicación${newPublicationIds.length === 1 ? "" : "es"} nueva${newPublicationIds.length === 1 ? "" : "s"}`
+            : "todo el investigador";
       } else {
         scope = "todo el investigador";
       }
-      if (isAuthenticated && ids?.length) {
+      if (isAuthenticated) {
-        setPublications((prev) => markPublicationsAsDownloaded(prev, ids));
+        const downloadedIds =
+          ids?.length > 0 ? ids : publications.map((p) => p.id);
+        setPublications((prev) =>
+          markPublicationsAsDownloaded(prev, downloadedIds),
+        );
       }
 
       toast.success(`Exportación ${format.toUpperCase()} completada`, {

frontend/src/pages/GroupResultsPage.jsx

@@ -182,18 +182,14 @@ export function GroupResultsPage() {
       return;
     }
 
-    const ids = isAuthenticated ? allNewIds : allIds;
+    const ids =
+      isAuthenticated && allNewIds.length > 0 ? allNewIds : allIds;
     if (ids.length === 0) {
-      toast.info(
+      toast.info("No hay publicaciones para exportar", {
-        isAuthenticated
-          ? "No hay publicaciones nuevas"
-          : "No hay publicaciones para exportar",
-        {
         id: GLOBAL_EXPORT_TOAST_ID,
         description:
           "No se encontraron publicaciones en los investigadores cargados.",
-        },
+      });
-      );
       return;
     }
 
@@ -253,7 +249,8 @@ export function GroupResultsPage() {
     const until = cardExportCooldownUntilRef.current[orcidId] ?? 0;
     if (now < until) return;
 
-    const ids = isAuthenticated ? newIds : totalIds;
+    const ids =
+      isAuthenticated && newIds.length > 0 ? newIds : totalIds;
     if (ids.length === 0) {
       toast.info("No hay publicaciones para exportar", {
         id: `group-export-card-${orcidId}`,
@@ -552,10 +549,7 @@ function CardExportButton({
   exportCooldownActive,
 }) {
   const isBusy = Boolean(exporting);
-  const disabled =
+  const disabled = isBusy || exportCooldownActive;
-    isBusy ||
-    exportCooldownActive ||
-    (isAuthenticated && !hasNew && totalCount > 0 && newCount === 0);
 
   let label;
   if (isBusy) {