support precompile as a verifier

modules/passkey/contracts/WebAuthnSigner.sol

@@ -62,6 +62,8 @@ contract WebAuthnSigner is SignatureValidator {
  * @dev A factory contract for creating and managing WebAuthn signers.
  */
 contract WebAuthnSignerFactory is ICustom256BitECSignerFactory, SignatureValidatorConstants {
+    address private constant SECP256R1_PRECOMPILE_ADDRESS = address(0x0b);
+
     // @inheritdoc ICustom256BitECSignerFactory
     function getSigner(uint256 qx, uint256 qy, address verifier) public view override returns (address signer) {
         bytes32 codeHash = keccak256(abi.encodePacked(type(WebAuthnSigner).creationCode, qx, qy, uint256(uint160(verifier))));
@@ -85,7 +87,8 @@ contract WebAuthnSignerFactory is ICustom256BitECSignerFactory, SignatureValidat
      */
     function _validVerifier(address verifier) internal view returns (bool) {
         // The verifier should contain code (The only way to implement a webauthn verifier is with a smart contract)
-        return !_hasNoCode(verifier);
+        // or be the precompile address for the secp256r1 curve defined in the RIP-7212
+        return !_hasNoCode(verifier) || verifier == SECP256R1_PRECOMPILE_ADDRESS;
     }
 
     // @inheritdoc ICustom256BitECSignerFactory