feat(welcome): add Albert G. testimonial (#529)

## What

Adds a new landing-page testimonial from **Albert G.**, sourced from a
user email.

- `welcome.tsx` — new entry (English source string) inserted before the
co-owner entry.
- `lang/es.json` — matching Spanish translation.

## Notes

- `gravatar` is the md5 of the sender's email.
- Adapted the message to fit: kept the praise (intuitive, functional,
daily-finance help, generous free tier), dropped the feature-request
portion (advanced auto-categorization, richer dashboards) since that's
roadmap feedback, not testimonial copy.

## Verification

- `LocalizationTest` passes (es.json key present, valid JSON).
- Prettier + ESLint clean.

lang/es.json

@@ -2026,5 +2026,6 @@
     "I love this project!": "¡Me encanta este proyecto!",
     "I'm genuinely happy using an open-source project with a real commitment to privacy — that's exactly what I want from a finance app.": "Estoy realmente contento usando un proyecto open-source con un compromiso real con la privacidad: es exactamente lo que quiero de una app de finanzas.",
     "I can't wait to discover everything the app can do. Thank you — it must have taken a tremendous effort. Congratulations!": "Con muchas ganas de ir descubriendo todo lo que se puede hacer con la aplicación. ¡Gracias! Debe haber sido un esfuerzo tremendo. ¡Enhorabuena!",
+    "The app is intuitive, functional, and a real help for managing my finances day to day. What stands out most is how much the free version offers — it really shows your commitment to your users. I’ll keep recommending it!": "La aplicación es intuitiva, funcional y de gran ayuda para gestionar mis finanzas en el día a día. Lo que más destaca es la cantidad de opciones de la versión gratuita: demuestra vuestro compromiso con los usuarios. ¡Seguiré recomendándola!",
     "I built the app I needed to make better decisions. Understanding how I spend and where my income comes from has brought me real financial peace of mind.": "He construido la app que necesitaba para tomar mejores decisiones. Entender cómo gasto y de dónde vienen mis ingresos me ha dado una verdadera tranquilidad financiera."
 }

resources/js/pages/welcome.tsx

@@ -1983,6 +1983,13 @@ export default function Welcome({
                 "I can't wait to discover everything the app can do. Thank you — it must have taken a tremendous effort. Congratulations!",
             ),
         },
+        {
+            name: 'Albert G.',
+            gravatar: 'bb92a036f4feb9d12d0a70dd2d9a5c5f',
+            text: __(
+                'The app is intuitive, functional, and a real help for managing my finances day to day. What stands out most is how much the free version offers — it really shows your commitment to your users. I’ll keep recommending it!',
+            ),
+        },
         {
             name: 'Víctor Falcón (co-owner)',
             gravatar: '50901af884c50a8f12804b0cf3aeb98a',