feat(invitations): reenviar invitaciones pendientes desde admin

Backend:
- client-invitations.service.ts: funcion resendInvitation() que
  genera nuevo token, actualiza expiresAt y reenvia el email.
- Controller + routes: POST /invitations/client/:id/resend

Frontend:
- API client + hook useResendInvitation con invalidacion de cache.
- Pagina /admin/invitar-cliente: boton 'Reenviar' por cada
  invitacion pendiente en la tabla.

Refs: docs/CAMBIOS-2026-05-09.md

apps/web/app/(dashboard)/admin/invitar-cliente/page.tsx

@@ -2,7 +2,7 @@
 
 import { useState } from 'react';
 import { Header } from '@/components/layouts/header';
-import { useCreateInvitation, useClientInvitations } from '@/lib/hooks/use-client-invitations';
+import { useCreateInvitation, useClientInvitations, useResendInvitation } from '@/lib/hooks/use-client-invitations';
 import { Button, Input, Card, CardContent, CardHeader, CardTitle } from '@horux/shared-ui';
 import { format } from 'date-fns';
 import { es } from 'date-fns/locale';
@@ -14,6 +14,7 @@ export default function InvitarClientePage() {
   const [message, setMessage] = useState<{ kind: 'ok' | 'error'; text: string } | null>(null);
 
   const createMut = useCreateInvitation();
+  const resendMut = useResendInvitation();
   const { data: invitations, isLoading } = useClientInvitations();
 
   const handleSubmit = async (e: React.FormEvent) => {
@@ -114,6 +115,7 @@ export default function InvitarClientePage() {
                       <th className="pb-2 font-medium">Estado</th>
                       <th className="pb-2 font-medium">Enviada</th>
                       <th className="pb-2 font-medium">Expira</th>
+                      <th className="pb-2 font-medium"></th>
                     </tr>
                   </thead>
                   <tbody>
@@ -128,6 +130,18 @@ export default function InvitarClientePage() {
                         <td className="py-2 text-muted-foreground">
                           {format(new Date(inv.expiresAt), 'dd MMM yyyy', { locale: es })}
                         </td>
+                        <td className="py-2">
+                          {inv.status === 'pending' && (
+                            <Button
+                              variant="ghost"
+                              size="sm"
+                              onClick={() => resendMut.mutate(inv.id)}
+                              disabled={resendMut.isPending}
+                            >
+                              {resendMut.isPending && resendMut.variables === inv.id ? 'Reenviando...' : 'Reenviar'}
+                            </Button>
+                          )}
+                        </td>
                       </tr>
                     ))}
                   </tbody>