Refactor biometric registration and optimize camera initialization

[fabriciolima]

• Refactored QR Biometric registration to use the QRCodeCapture system
• Added registration counters to menu items
• Optimized camera initialization during boot
• Fixed rotation issue on boot
• Hid redundant biometric unlock toggle

What is this PR for?

Changes made to:

• Code
• Tests
• Docs
• CHANGELOG

Did you build the code and tested on device?

• Yes, build and tested on

What is the purpose of this pull request?

• Bug fix
• New feature
• Docs update
• Other

[fabriciolima]

Added a biometric feature that allows using a QR code to unlock Krux.
If a biometric is registered, the camera is initialized and the Krux symbol is NOT displayed.
Great for airports… I mean, curious eyes.

[odudex]

QR Code "unlocking" is an interesting opsec idea, but both the terms "unlocking" and "biometric" are misleading here.

Although tamper check code at boot can block booting from the UI, Krux can't be locked, it does not have a PIN. So, you have to be familiar with Tamper Check Code limitations.

Biometrics (metrics from biological elements) cover fingerprint, facial, iris recognition, etc. So it's not the case here.

Having that said, I think this idea can evolve when code, terms and concepts become more precise and concise.

[fabriciolima]

thanks for reply i made this to solve a pain that i have. I have thinked in add gests and writing but this solved my problem
Feel free to use the code

[tadeubas]

Hey @fabriciolima, nice idea! I traveled quite a bit a few months ago and I know how important this feature is. Users have been asking for this for a long time in the Krux Telegram chat, and there’s also an open GitHub issue about inconspicuous startup dating back to April 2023 #203

I started developing the idea of running Krux apps about a year ago, and it’s now ready to be merged #485

The PR #485 intentionally does not address inconspicuous startup, to keep the scope smaller and improve the chances of being merged sooner. It currently includes a Nostr app and a Steganography app. The long-term idea is to have several apps available, such as a game or a QR reader, to improve OPSEC.

If you have time, please test the Krux apps PR #485 and share your feedback. Hopefully, one day this will be available to every Krux user.