Upgrade: Angular 18, Ionic 8, Capacitor 6

Modernizacion completa del frontend:

- Angular 8 -> 18.2.14
- Ionic 4 -> 8.7.17
- Capacitor 6.x (migracion desde Cordova/@ionic-native)
- TypeScript 5.4.5
- Swiper 11 con Web Components API

Cambios principales:
- Migrar NativeStorage a @capacitor/preferences
- Migrar InAppBrowser a @capacitor/browser
- Migrar Camera a @capacitor/camera
- Migrar Geolocation a @capacitor/geolocation
- Migrar StatusBar/SplashScreen a Capacitor
- Migrar Facebook/Google login a plugins Capacitor
- Actualizar lazy loading syntax (Angular 12+)
- Configurar buildOptimizer: false para Ionic 8
- Limpiar package.json de dependencias obsoletas
- Agregar README con guia de instalacion

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

src/app/services/env.service.ts

@@ -4,7 +4,10 @@ import { Injectable } from '@angular/core';
   providedIn: 'root'
 })
 export class EnvService {
-  API_URL = 'https://ichamba-1562349005909.uc.r.appspot.com/api/';
+  // Usa el mismo host pero puerto 8080 para el API
+  API_URL = (typeof window !== 'undefined' && window.location.hostname !== 'localhost')
+    ? `http://${window.location.hostname}:8080/api/`
+    : 'http://localhost:8080/api/';
   SECRET = 'wBIIKuDbrxNKzQhAUGiZLoaoQ4MichAN3wP2AP7B';
   MERCHANT_ID = 'm9k4beuso5az0wjqztvt';
   PUBLIC_API_KEY = 'pk_9465179493384689a8d2da9adc825411';