Add support authentication credentials caching

[MCarlomagno]

Description

Added support to authenticate using apiKey + accessToken (instead of apiSecret). This feature is supported in relay signer package only, but extendable to other packages too.

How it works

Now we expose getApiKey() & getAccessToken() functions, these credentials can be reused in other Defender SDK instances. This process skips authentication endpoints but devs must setup their own refresh process or the client will throw Unauthorized after the token was expired ⚠️

Example

  const creds = {
    relayerApiKey: process.env.RELAYER_API_KEY,
    relayerApiSecret: process.env.RELAYER_API_SECRET,
  };
  const client = new Defender(creds);

  const relayerApiKey = client.relaySigner.getApiKey();
  const accessToken = await client.relaySigner.getAccessToken();
  const cachedSession = { relayerApiKey, accessToken };
  
  ...  

  // Another Defender instance running in any other environment
  const client = new Defender(cachedSession);
  const info = await client.relaySigner.getRelayerStatus();

[changeset-bot]

⚠️ No Changeset found

Latest commit: d5a26c9

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[socket-security]

New dependencies detected. Learn more about Socket for GitHub ↗︎

Package	New capabilities	Transitives	Size	Publisher
npm/@openzeppelin/defender-sdk@1.13.1	Transitive: environment, filesystem	+10	903 kB	collins-oz

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[tirumerla]

Should we still need this, may be it's better to keep this branch and close the pr and revisit it later now that we have auth caching being done on the BE