Migrar backend a PostgreSQL + Node.js/Express con nuevas funcionalidades

Backend (water-api/):
- Crear API REST completa con Express + TypeScript
- Implementar autenticación JWT con refresh tokens
- CRUD completo para: projects, concentrators, meters, gateways, devices, users, roles
- Agregar validación con Zod para todas las entidades
- Implementar webhooks para The Things Stack (LoRaWAN)
- Agregar endpoint de lecturas con filtros y resumen de consumo
- Implementar carga masiva de medidores via Excel (.xlsx)

Frontend:
- Crear cliente HTTP con manejo automático de JWT y refresh
- Actualizar todas las APIs para usar nuevo backend
- Agregar sistema de autenticación real (login, logout, me)
- Agregar selector de tipo (LORA, LoRaWAN, Grandes) en concentradores y medidores
- Agregar campo Meter ID en medidores
- Crear modal de carga masiva para medidores
- Agregar página de consumo con gráficas y filtros
- Corregir carga de proyectos independiente de datos existentes

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

water-api/src/routes/concentrator.routes.ts

@@ -0,0 +1,59 @@
+import { Router } from 'express';
+import { authenticateToken } from '../middleware/auth.middleware';
+import {
+  validateCreateConcentrator,
+  validateUpdateConcentrator,
+} from '../validators/concentrator.validator';
+import * as concentratorController from '../controllers/concentrator.controller';
+
+const router = Router();
+
+/**
+ * GET /concentrators
+ * Get all concentrators with optional filters and pagination
+ * Query params: project_id, status, page, limit, sortBy, sortOrder
+ * Protected endpoint - requires authentication
+ */
+router.get('/', authenticateToken, concentratorController.getAll);
+
+/**
+ * GET /concentrators/:id
+ * Get a single concentrator by ID with gateway count
+ * Protected endpoint - requires authentication
+ */
+router.get('/:id', authenticateToken, concentratorController.getById);
+
+/**
+ * POST /concentrators
+ * Create a new concentrator
+ * Body: { serial_number, name?, project_id, location?, status?, ip_address?, firmware_version? }
+ * Protected endpoint - requires authentication
+ */
+router.post(
+  '/',
+  authenticateToken,
+  validateCreateConcentrator,
+  concentratorController.create
+);
+
+/**
+ * PUT /concentrators/:id
+ * Update an existing concentrator
+ * Body: { serial_number?, name?, project_id?, location?, status?, ip_address?, firmware_version? }
+ * Protected endpoint - requires authentication
+ */
+router.put(
+  '/:id',
+  authenticateToken,
+  validateUpdateConcentrator,
+  concentratorController.update
+);
+
+/**
+ * DELETE /concentrators/:id
+ * Delete a concentrator (fails if gateways are associated)
+ * Protected endpoint - requires authentication
+ */
+router.delete('/:id', authenticateToken, concentratorController.remove);
+
+export default router;