[feat] [biometric] Adding the capability of encrypting/decrypting data using biometric authentication on Android (Ref. #2306)

[charlesschaefer]

I've used the current structure of the biometric plugin to use Android's capability of encrypting/decrypting data using a key that can only be accessible when the user successfully authenticates with their registered biometric methods.

More details on the need of this change can be found on the #2306 issue.

Summary of changes:
Kotlin

• Created the command biometricCipher that will be responsible to encrypt/decrypt data by asking the user for their biometric authentication and, when successful, get a key from android device to make the cryptography process.
• Extracted some common code to their own functions.
• Changed the AuthOptions class to include the fields dataToEncrypt and dataToDecrypt
• Changed the force of authentication methods when using cryptography. Android allows using this feature only when using STRONG methods. When not using cryptography, we'll keep allowing the use of WEAK methods.

JS

• Added the method biometricCipher
• Changed the AuthOptions interface to include the fields dataToEncrypt and dataToDecrypt

Rust

• Changed the AuthOptions struct to include the fields data_to_encrypt and data_to_decrypt
• Added the CipherResult struct
• Added the method Biometric.biometric_cipher() to access the similar method on Kotlin's side.

Some implementation notes:

• I've used a fixed crypto algorythm instead of allowing the consumer to define it (AED with GCM block mode).
• I detect that the consumer wants to encrypt/decrypt data only by the presence of the fields dataToEncrypt/dataToDecrypt on the AuthOptions object sent by them.
• The flow is: the consumer can use the authenticate command as usual (if doesn't want to use cryptography) or can use the biometricCipher command (both after checking with the status command) passing the raw data to encrypt or the encrypted data to decrypt.
• If the key used before to encrypt some raw data is not valid anymore, it will return an error (using the same authenticateResult method that is used with authenticate command).

I'll need some guidance about where to change the site's documentation to include this new method.