fix: Prevent manual tracking of internal events that are automatically tracked

apps/api/src/controllers/Actions.ts

@@ -55,6 +55,21 @@ export class Actions {
     // Zod validation - errors automatically handled by global error handler
     const {event, email, subscribed, data} = ActionSchemas.track.parse(req.body);
 
+    // Prevent manual tracking of reserved system events
+    if (EventService.isReservedEvent(event)) {
+      throw new ValidationError(
+        [
+          {
+            field: 'event',
+            message: `Event name "${event}" is reserved for system use and cannot be manually tracked`,
+            code: 'reserved_event',
+            received: event,
+          },
+        ],
+        'Cannot track reserved system event',
+      );
+    }
+
     // Create or update contact with persistent data only
     // ContactService.upsert will filter out non-persistent fields
     const contact = await ContactService.upsert(