feat: Stripe Checkout, Zeptomail, pre-alert linking, perfil 3-tab, carga-pesada landing

- payments: real Stripe Checkout Session (redirect flow), confirmBySession, webhook handler
- notifications: Zeptomail REST email, wa.me WhatsApp links, IntegrationsService injection
- auth: changePassword, updateProfile, disableMfa (TOTP-verified) endpoints
- packages: tryLinkPreAlert() auto-links on create (non-blocking)
- integrations: catalog updated (zeptomail, stripe_webhook_secret; removed sendgrid/whatsapp-api)
- web/portal/perfil: 3-tab layout (datos / contraseña / MFA)
- web/portal/pago: Stripe redirect + ?success=1&session_id= callback, cancelled banner
- web/admin/b2b: fix enum values (EN_COTIZACION, ACEPTADO)
- web/carga-pesada: rich marketing landing (FCL/LCL, 7-step process, sectors, INEN callout)
- tests: fix payments.service.spec (IntegrationsService+ConfigService mocks)
- tests: fix notifications.service.spec (IntegrationsService mock, phone in mockUser)
- all 104 tests passing, API + web builds clean

pnpm-lock.yaml

@@ -71,6 +71,9 @@ importers:
       rxjs:
         specifier: ^7.8.2
         version: 7.8.2
+      stripe:
+        specifier: ^22.2.0
+        version: 22.2.0(@types/node@22.19.19)
     devDependencies:
       '@nestjs/cli':
         specifier: ^11.0.7
@@ -2889,6 +2892,15 @@ packages:
     resolution: {integrity: sha512-6fPc+R4ihwqP6N/aIv2f1gMH8lOVtWQHoqC4yK6oSDVVocumAsfCqjkXnqiYMhmMwS/mEHLp7Vehlt3ql6lEig==}
     engines: {node: '>=8'}
 
+  stripe@22.2.0:
+    resolution: {integrity: sha512-WFGpMOom9QZqso1kcnSwJsCdC1QHDlMoCOxBZRf3JraMzhkfw7dgSdD2a1CFZrqC+mzAfqeEtYILrZhWKIDruA==}
+    engines: {node: '>=18'}
+    peerDependencies:
+      '@types/node': '>=18'
+    peerDependenciesMeta:
+      '@types/node':
+        optional: true
+
   strtok3@10.3.5:
     resolution: {integrity: sha512-ki4hZQfh5rX0QDLLkOCj+h+CVNkqmp/CMf8v8kZpkNVK6jGQooMytqzLZYUVYIZcFZ6yDB70EfD8POcFXiF5oA==}
     engines: {node: '>=18'}
@@ -6230,6 +6242,10 @@ snapshots:
 
   strip-json-comments@3.1.1: {}
 
+  stripe@22.2.0(@types/node@22.19.19):
+    optionalDependencies:
+      '@types/node': 22.19.19
+
   strtok3@10.3.5:
     dependencies:
       '@tokenizer/token': 0.3.0