fix: [WLEO-339] Add function to remove leading zero from base64url encoded JWK properties

[manuraf]

Warning

Breaking change for IT Wallet!

List of Changes

• New helper function, fixBase64WithLeadingZero (with its underlying helper, removeLeadingZeroAndParseB64Url), to sanitize JSON Web Key (JWK) properties. It addresses potential issues with cryptographic operations by processing the base64url encoded key components (x, y, e, and n). The new functions decode the input, remove any unwanted leading zero, and then re-encode the result to ensure proper formatting.
• It replace fixBase64EncodingOnKey inside CryptoContext

Motivation and Context

The method getPublicKey in the io-react-native-crypto library returns a key with coordinates in base64 format. This base64 format is generated by converting hex to base64 internally, but sometimes the conversion does not conform to the P-256 key standard—which requires exactly 32 bytes—because the hex representation may result in 33 bytes.

The problem stems from the behavior of BigInteger.toByteArray, which, in certain contexts (e.g., ASN.1 DER signatures), prepends a 0x00 byte if the coordinate starts with a value greater than 0x7F to avoid it being interpreted as a negative number.
This PR aims to temporarily bypass the issue within this library by ensuring that any unwanted leading zero is removed during the conversion process.

How Has This Been Tested?

• Re-issuance Wallet Instance and PID
• Try a PID Presentation, it should work as the same

Screenshots (if appropriate):

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.