feat(clientes-maestro): importar y exportar clientes del archivo maestro

- Tabla ClienteMaestro (27 campos, unique numCliente)
- Importador Excel: 1535 clientes del Reporte maestro
- API: listar/filtros/exportar/detalle/importar
- Frontend: tabla paginada, filtros, exportar Excel
- Dark mode completo, 52 tests verdes

api-gateway/src/routes/index.ts

@@ -115,6 +115,13 @@ import {
   importarEndpoint as importarCapturaEndpoint,
   requireAdminCaptura,
 } from '../controllers/captura-departamento.controller.js'
+import {
+  listarEndpoint as listarMaestroEndpoint,
+  exportarEndpoint as exportarMaestroEndpoint,
+  obtenerEndpoint as obtenerMaestroEndpoint,
+  importarEndpoint as importarMaestroEndpoint,
+  requireAdmin as requireAdminMaestro,
+} from '../controllers/cliente-maestro.controller.js'
 
 export const apiRouter = Router()
 
@@ -257,3 +264,10 @@ apiRouter.post('/captura/importar', requireAdminCaptura, importarCapturaEndpoint
 apiRouter.get('/push/vapid-key', vapidKeyEndpoint)
 apiRouter.post('/push/suscribir', suscribirEndpoint)
 apiRouter.post('/push/desuscribir', desuscribirEndpoint)
+
+// ── Clientes Maestro ──────────────────────────────────────────────
+apiRouter.get('/clientes-maestro', listarMaestroEndpoint)
+// Exportar va ANTES de /:numCliente para no colisionar con el parámetro
+apiRouter.get('/clientes-maestro/exportar', exportarMaestroEndpoint)
+apiRouter.get('/clientes-maestro/:numCliente', obtenerMaestroEndpoint)
+apiRouter.post('/clientes-maestro/importar', requireAdminMaestro, importarMaestroEndpoint)