ui/ux: Going 'back' from Storage location setup exits the app

[Zvonimir-FUTO]

Reproduction rate:

0. Launch the app once and go through initial setup
1. Open Settings
2. Under Storage tap on Storage location
3. Go 'back' via gesture navigation or button navigation
   3.5 For other variation you can press on Cancel and will return you to Home screen instead of Settings

Expected Result:
App returns you back to settings.

Actual Result:
App exits.

Platform Info:
Pixel 9a
GrapheneOS
Android 17
FUTO Notes v1.7.0

[SomewhatJustin]

Good catch! We'll work on this.