feat: added isPassKeyAvailable on biometric-ed25519 package

[hcho112]

Pre-flight checklist

• I have read the Contributing Guidelines on pull requests.
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• If this is a code change: I have written unit tests.
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• If this is a new API or substantial change: the PR has an accompanying issue (closes #0000) and the maintainers have approved on my working plan.

Motivation

This PR contains a new util function isPassKeyAvailable where it will be used to validate the availability of passKey usage of user's current browser.

Test Plan

I have conducted manual test on running above code on latest Chrome browser (returns promise true) vs latest Firefox (returns promise false)

[changeset-bot]

🦋 Changeset detected

Latest commit: 4f7f890

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@near-js/biometric-ed25519	Minor

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[andy-haynes]

Looks good, one small comment on the util function

[andy-haynes]

Suggested change

	if (!PublicKeyCredential || !PublicKeyCredential?.isUserVerifyingPlatformAuthenticatorAvailable) {
	return Promise.resolve(false);
	}
	return PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
	return PublicKeyCredential?.isUserVerifyingPlatformAuthenticatorAvailable?.() || false;

The return value of an async function is always a Promise, so it doesn't need to be wrapped in Promise.resolve. Also you can use optional chaining to call the PublicKeyCredential method to avoid needing to reference it more than once 🙂

[hcho112]

would this still work if PublicKeyCredential is not available? From Ref, on WebView Android, it doesn't support at all. Assuming that PublicKeyCredential can be undefined, should we use

if (typeof PublicKeyCredential !== 'undefined') {
  return PublicKeyCredential?.isUserVerifyingPlatformAuthenticatorAvailable?.();
}
return false;

[andy-haynes]

would this still work if PublicKeyCredential is not available?

👍 if it's an invalid reference then it must be guarded.

Other alternatives to your solution would be a try/catch or, my personal preference, referencing via window, i.e.

return window.PublicKeyCredential?.isUserVerifyingPlatformAuthenticatorAvailable?.() || false;