Theme selection not respected on autofill and reverts to System Default

### Bitwarden Beta

- [X] I'm using the new native Bitwarden Beta app and I'm aware that legacy .NET app bugs should be reported in [bitwarden/mobile](https://github.com/bitwarden/mobile)

### Steps To Reproduce

1. Set Bitwarden theme to Dark mode
2. Close bitwarden app
3. Set System default theme to light mode
4. Go to autofill a password in any app
5. Bitwarden splash / faceID screen shows as Light mode

### Expected Result

The autofill screen should respect the darkmode setting set in the bitwarden app instead of reverting to system default.

### Actual Result

The users theme selection is not respected and reverts to system default

### Screenshots or Videos


### Additional Context

_No response_

### Build Version

2024.8.1 (1052)

### Environment Details

- IPhone 13 Pro
- iOS 17.6.1

### Issue Tracking Info

- [X] I understand that work is tracked outside of Github. A PR will be linked to this issue should one be opened to address it, but Bitwarden doesn't use fields like "assigned", "milestone", or "project" to track progress.

Reproduce the issue in the native Bitwarden Beta app using the listed iPhone and iOS versions: set Bitwarden to Dark mode, switch the system to Light mode, then open autofill. Trace the autofill splash and Face ID screen's theme selection; done means they retain the app's Dark mode instead of reverting to System Default.

Written by the indexing model from the issue text.