[BWA-245] Bitwarden Auth still uses old color palette here and there

### Steps To Reproduce

1. Install the bitwarden authenticator app
2. enable dark mode
3. navigate through different screens

### Expected Result

Have the same color(palette) throughout the whole app. (Match design with the bitwarden password manager app)

### Actual Result

There are some leftovers from the native app release in 2024. After that, bitwarden had several redesigns but at some points, the authenticator app still looks like the 2024 version of bitwarden.

### Screenshots or Videos

### Additional Context

The grey doesn’t fit in bitwarden’s current design language. Also I believe it is not supposed to still be in the app.

### Build Version

2026.3.1

### What server are you connecting to?

US

### Self-host Server Version

_No response_

### Environment Details

tested on:
iPhone 16 Pro, running latest iOS 26.4.1
iPad Pro 11“ with M2 Chip, running iPadOS 26.4

### 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.

Start by reproducing the dark-mode screens on the listed iPhone and iPad environments, then compare the screenshots with the current Bitwarden Password Manager design. Identify each remaining 2024-era gray or mismatched palette element across the Authenticator app and update the affected screens so the palette is consistent throughout.

Written by the indexing model from the issue text.