Flatpak writes to ~/cake_wallet and has access to the home directory
**Describe the bug**

The Flatpak desktop version of Cake creates the ~/cake_wallet directory and stores the majority of the application data there.

This unnecessarily litters the home directory. However, a bigger problem is that due to this the Cake Flatpak comes with full access permission to the whole home directory by default, without your knowledge or consent.

One of the points of Flatpak is that applications can be built in a way that you don't have to take the the risk of giving access to all your files.

Can you constrain Cake's working directory to ~/.var/app/com.cakewallet.CakeWallet, where Flatpaks usually store their application data, and remove the default permission to the home folder?

**Platform:**
 - OS: Linux
 - Cake Wallet Version: v4.19.5 Flatpak
