Offerbook is being deleted

As per the app logs it seems offerbook data is being deleted and recreated. The data should persis, and only be updated. 

```
[1] 🔄 [auto_1768908713752_9ko8g] Triggering manual offerbook sync (auto)...
[1] 🗑️ Deleting old offerbook.json...
[1] 📝 Creating fresh empty offerbook.json...
```