Enhance debug logging and Cross-Device support for Passkey Registration

Update the registrieren.vue component to include detailed debug statements for the Cross-Device authentication flow, specifically during QR-Code generation. Improve logging in the register-passkey-options and register-passkey APIs to capture request details such as user agent and IP address, aiding in troubleshooting. Additionally, introduce a new function to retrieve pre-registration data, enhancing the overall registration process and compliance with Cross-Device requirements.

server/api/auth/register-passkey.post.js

@@ -15,16 +15,27 @@ export default defineEventHandler(async (event) => {
   const userAgent = getHeader(event, 'user-agent')
   const { origin: webauthnOrigin } = getWebAuthnConfig()
   
-  console.log('[DEBUG] ===== register-passkey request received =====')
+  console.log('')
+  console.log('='.repeat(80))
+  console.log('[DEBUG] 🔑 ===== PASSKEY REGISTRATION REQUEST RECEIVED =====')
+  console.log('='.repeat(80))
   console.log('[DEBUG] Request Details:', {
-    origin: requestOrigin,
+    origin: requestOrigin || 'none',
     webauthnOrigin,
-    userAgent: userAgent?.substring(0, 150),
+    userAgent: userAgent?.substring(0, 150) || 'none',
     timestamp: new Date().toISOString(),
     method: getMethod(event),
     ip: getClientIp(event),
-    note: 'Dieser Request sollte vom Smartphone kommen, wenn der QR-Code gescannt wurde'
+    url: getRequestURL(event).href,
+    path: getRequestURL(event).pathname
   })
+  console.log('[DEBUG] ⚠️ WICHTIG: Dieser Request sollte vom Smartphone kommen, wenn der QR-Code gescannt wurde')
+  console.log('[DEBUG] ⚠️ Wenn dieser Request NICHT im Log erscheint, bedeutet das:')
+  console.log('[DEBUG]   1. Das Smartphone konnte die Website nicht erreichen')
+  console.log('[DEBUG]   2. Oder startRegistration auf dem Smartphone ist fehlgeschlagen')
+  console.log('[DEBUG]   3. Oder die Credential-Response wurde nicht gesendet')
+  console.log('='.repeat(80))
+  console.log('')
   console.log('[DEBUG] User-Agent Analysis:', {
     isMobile: /Mobile|Android|iPhone|iPad/i.test(userAgent || ''),
     isChrome: /Chrome/i.test(userAgent || ''),