fix: use existing services instance in birthday-setup

**Motivations :**
- Chaque page créait une nouvelle instance des services, causant des problèmes de synchronisation
- Le wallet disparaissait entre les pages à cause de cette incohérence
- Il faut utiliser l'instance existante des services pour maintenir la cohérence

**Modifications :**
- Suppression de la boucle d'attente pour l'initialisation des services
- Utilisation directe de Services.getInstance() pour obtenir l'instance existante
- Simplification du code d'initialisation des services

**Pages affectées :**
- src/pages/birthday-setup/birthday-setup.ts (utilisation de l'instance existante)

src/pages/birthday-setup/birthday-setup.ts

@@ -26,33 +26,11 @@ document.addEventListener('DOMContentLoaded', async () => {
             if (!Services) {
                 throw new Error('Services class not found in default export');
             }
-            console.log('🔄 Waiting for services to be ready...');
+            console.log('🔄 Getting existing services instance...');
 
-            // Attendre que les services soient initialisés
-            let attempts = 0;
-            const maxAttempts = 30;
-            const delayMs = 2000;
-
-            let services;
-            while (attempts < maxAttempts) {
-                try {
-                    console.log(`🔄 Attempting to get services (attempt ${attempts + 1}/${maxAttempts})...`);
-                    services = await Services.getInstance();
-                    console.log('✅ Services initialized successfully');
-                    break;
-                } catch (error) {
-                    console.log(`⏳ Services not ready yet (attempt ${attempts + 1}/${maxAttempts}):`, (error as Error).message);
-                    attempts++;
-                    if (attempts >= maxAttempts) {
-                        throw new Error(`Services failed to initialize after ${maxAttempts} attempts.`);
-                    }
-                    await new Promise(resolve => setTimeout(resolve, delayMs));
-                }
-            }
-
-            if (!services) {
-                throw new Error('Services not initialized');
-            }
+            // Utiliser l'instance existante des services
+            const services = await Services.getInstance();
+            console.log('✅ Services instance obtained successfully');
 
             // Connexion aux relais
             await services.connectAllRelays();