Only one Sighnstation can connect

server.js

@@ -205,6 +205,20 @@ function handleMasterRegister(ws) {
 }
 
 function handleSignatureRegister(ws) {
+    // Check if another signature station is already connected
+    if (signatureConnection && signatureConnection.readyState === WebSocket.OPEN) {
+        // Inform the new station that another station is already connected
+        ws.send(JSON.stringify({
+            type: 'already_connected'
+        }));
+        console.log('⚠️ Neue Signatur-Station versucht sich zu verbinden, aber bereits eine Station verbunden');
+        console.log('⚠️ Neue Station wurde informiert, alte Station bleibt aktiv');
+        // Keep the old connection, don't replace it
+        // Don't register the new connection as signatureConnection
+        return; // Exit without registering the new connection
+    }
+
+    // No existing connection, register this new one
     signatureConnection = ws;
     console.log('Signatur-Station registriert');