feat: deep SEO optimization — metadata, OG tags, sitemap, structured data, GA4

- Add metadataBase and localized generateMetadata to all pages (EN/FR)
- Add Open Graph and Twitter card defaults with branded OG image
- Add canonical URLs and hreflang alternates on every page
- Create robots.ts (allow all, block /admin/ and /api/)
- Create sitemap.ts with all routes x 2 locales and hreflang
- Add Organization, WebSite, and CreativeWork JSON-LD structured data
- Add GA4 (G-LD348WF8EM) with Consent Mode v2 (default denied for EEA)
- Add llms.txt for AI discoverability
- Add production nginx config for letsbe.biz

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/i18n/messages/en.json

@@ -1,4 +1,33 @@
 {
+  "meta": {
+    "siteName": "LetsBe.",
+    "home": {
+      "title": "LetsBe. | Custom Web Design, Software & Digital Infrastructure",
+      "description": "Bespoke websites, purpose-built software, AI integration, and private infrastructure — designed, built, and managed by one dedicated team."
+    },
+    "about": {
+      "title": "About LetsBe. | Our Story & Approach",
+      "description": "An American-founded digital studio building custom websites, software, and platforms for businesses that care about quality."
+    },
+    "services": {
+      "title": "Services | LetsBe. — Web Design, Software & Infrastructure",
+      "description": "Custom web design, purpose-built software, AI automation, and private infrastructure — three pillars of digital excellence under one roof."
+    },
+    "work": {
+      "monaco-ocean": {
+        "title": "Monaco Ocean Protection Challenge | LetsBe.",
+        "description": "AI-powered judging and analytics platform for one of the Mediterranean's leading conservation events."
+      },
+      "port-nimara": {
+        "title": "Port Nimara — Maritime Digital Hub | LetsBe.",
+        "description": "Custom website and full CRM for lead management, berth assignment, and marina operations."
+      },
+      "port-amador": {
+        "title": "Port Amador — Premium Nautical Experience | LetsBe.",
+        "description": "Website and private digital infrastructure for a premium marina — cloud storage, email, and file management."
+      }
+    }
+  },
   "nav": {
     "services": "Services",
     "configure": "Get Started",

src/i18n/messages/fr.json

@@ -1,4 +1,33 @@
 {
+  "meta": {
+    "siteName": "LetsBe.",
+    "home": {
+      "title": "LetsBe. | Design Web Sur Mesure, Logiciels & Infrastructure Digitale",
+      "description": "Sites web sur mesure, logiciels dédiés, intégration IA et infrastructure privée — conçus, développés et gérés par une seule équipe."
+    },
+    "about": {
+      "title": "À Propos de LetsBe. | Notre Histoire & Approche",
+      "description": "Un studio digital fondé aux États-Unis, créant des sites web, logiciels et plateformes sur mesure pour les entreprises exigeantes."
+    },
+    "services": {
+      "title": "Services | LetsBe. — Design Web, Logiciels & Infrastructure",
+      "description": "Design web sur mesure, logiciels dédiés, automatisation IA et infrastructure privée — trois piliers d'excellence digitale sous un même toit."
+    },
+    "work": {
+      "monaco-ocean": {
+        "title": "Monaco Ocean Protection Challenge | LetsBe.",
+        "description": "Plateforme de jugement et d'analyse propulsée par l'IA pour l'un des événements de conservation majeurs de la Méditerranée."
+      },
+      "port-nimara": {
+        "title": "Port Nimara — Hub Digital Maritime | LetsBe.",
+        "description": "Site web sur mesure et CRM complet pour la gestion des prospects, l'attribution des places et les opérations de la marina."
+      },
+      "port-amador": {
+        "title": "Port Amador — Expérience Nautique Premium | LetsBe.",
+        "description": "Site web et infrastructure digitale privée pour une marina premium — stockage cloud, email et gestion de fichiers."
+      }
+    }
+  },
   "nav": {
     "services": "Services",
     "configure": "Démarrer",