feat: enhance MainForm layout and user experience; add new components and improve form structure

feat: update i18n configuration to prioritize browser language; enhance language detection
feat: add new translation keys for form submission feedback in English and German

frontend/src/utils/i18n/index.ts

@@ -22,7 +22,7 @@ i18n
   .init({
     resources,
     fallbackLng: "en", // use en if detected lng is not available
-    lng: Cookies.get("language") || "en", // language to use, more information here: https://www.i18next.com/overview/configuration-options#languages-namespaces-resources
+    lng: Cookies.get("language") || navigator.language.split("-")[0] || "en", // Check cookie first, then browser language
     // you can use the i18n.changeLanguage function to change the language manually: https://www.i18next.com/overview/api#changelanguage
     // if you're using a language detector, do not define the lng option
 

frontend/src/utils/i18n/locales/de/de.json

@@ -11,5 +11,12 @@
     "submit": "Kaufen",
     "failed-to-load-users": "Das Laden der Benutzer ist fehlgeschlagen.",
     "user": "Benutzer",
-    "next-id": "Nächste Eintragsnummer: "
+    "next-id": "Nächste Eintragsnummer: ",
+    "form-submitted-successfully": "Formular erfolgreich übermittelt!",
+    "orm-submission-failed": "Formularübermittlung fehlgeschlagen.",
+    "success": "Erfolg",
+    "error": "Fehler",
+    "cash": "Bar",
+    "paypal": "PayPal",
+    "transfer": "Überweisung"
 }

frontend/src/utils/i18n/locales/en/en.json

@@ -11,5 +11,12 @@
     "submit": "Buy",
     "failed-to-load-users": "Failed to load users.",
     "user": "User",
-    "next-id": "Next Entry Number: "
+    "next-id": "Next Entry Number: ",
+    "form-submitted-successfully": "Form submitted successfully!",
+    "orm-submission-failed": "Form submission failed.",
+    "success": "Success",
+    "error": "Error",
+    "cash": "Cash",
+    "paypal": "PayPal",
+    "transfer": "Bank Transfer"
 }