feat: implement dynamic API base URL and add language toggle in MainForm

Co-authored-by: Copilot <copilot@github.com>

backend/routes/default/frontend.data.js

@@ -40,7 +40,7 @@ export const confirmUser = async (username) => {
     console.log(tableName);
 
     const [createTable] = await pool.query(
-      `CREATE TABLE IF NOT EXISTS ${tableName} (
+      `CREATE TABLE IF NOT EXISTS ? (
         id INT AUTO_INCREMENT PRIMARY KEY,
         Vorname VARCHAR(100) NOT NULL,
         Nachname Varchar(100) NOT NULL,
@@ -56,14 +56,16 @@ export const confirmUser = async (username) => {
         Plz_Ort Varchar(100),
         Zahlungsmethode Varchar(100),
         created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
-      )`
+      )`,
+      [tableName],
     );
 
     if (createTable) {
       let nextID;
       const getNextID = async () => {
         const [rows] = await pool.query(
-          `SELECT id FROM ${tableName} ORDER BY id DESC LIMIT 1`
+          `SELECT id FROM ? ORDER BY id DESC LIMIT 1`,
+          [tableName],
         );
         nextID = rows.length > 0 ? rows[0].id + 1 : 1;
       };
@@ -87,8 +89,9 @@ export const newEntry = async (formData, username) => {
   const tableName = confirmation.tableName;
 
   const [result] = await pool.query(
-    `INSERT INTO ${tableName} (Vorname, Nachname, EMail, Telefonnummer, Lose, Firmenname, Vorname_Geschaeftlich, Nachname_Geschaeftlich, EMail_Geschaeftlich, Telefonnummer_Geschaeftlich, Strasse_Hausnr, Plz_Ort, Zahlungsmethode) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
+    `INSERT INTO ? (Vorname, Nachname, EMail, Telefonnummer, Lose, Firmenname, Vorname_Geschaeftlich, Nachname_Geschaeftlich, EMail_Geschaeftlich, Telefonnummer_Geschaeftlich, Strasse_Hausnr, Plz_Ort, Zahlungsmethode) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
     [
+      tableName,
       formData.firstName,
       formData.lastName,
       formData.email,
@@ -102,7 +105,7 @@ export const newEntry = async (formData, username) => {
       formData.street,
       formData.postalCode,
       formData.paymentMethod,
-    ]
+    ],
   );
 
   return { success: true, insertId: result.insertId };