chore: final integration audit and logic hardening

apps/api/src/services/whatsapp.ts

@@ -217,8 +217,8 @@ export class WhatsAppService {
 
             await scheduleMessage(user.id, welcomeMsg);
 
-            const trackTitle = user.language === 'FR' ? "Comprendre Son Business (FR)" : "Comprendre Son Business (WOLOF)";
-            const defaultTrack = await prisma.track.findFirst({ where: { title: trackTitle } });
+            const trackId = user.language === 'FR' ? "T1-FR" : "T1-WO";
+            const defaultTrack = await prisma.track.findUnique({ where: { id: trackId } });
             if (defaultTrack) await enrollUser(user.id, defaultTrack.id);
             return;
         }