feat(web-i18n): add es/fr locales and expand switcher locale set

apps/web/src/messages/en.json

@@ -0,0 +1,19 @@
+{
+  "Home": {
+    "badge": "Web App",
+    "title": "Your Next.js CMS Frontend",
+    "description": "This page reads posts through the shared database package.",
+    "latestPosts": "Latest posts",
+    "explore": "Explore",
+    "noExcerpt": "No excerpt"
+  },
+  "LanguageSwitcher": {
+    "label": "Language",
+    "localeNames": {
+      "de": "German",
+      "en": "English",
+      "es": "Spanish",
+      "fr": "French"
+    }
+  }
+}