@turnkey/http: add withAsyncPolling(...) helper

[keyz-tk]

Summary & Motivation

All Turnkey mutation endpoints are asynchronous (with the exception of signing endpoints) because we support consensus via policy on all write actions. To simplify async mutations, this PR adds a withAsyncPolling(...) wrapper. Here's a quick example:

import {
  PublicApiService,
  withAsyncPolling,
  TurnkeyActivityError,
} from "@turnkey/http";

// Use `withAsyncPolling(...)` to wrap & create a fetcher with built-in async polling support
const fetcher = withAsyncPolling({
  request: PublicApiService.postCreatePrivateKeys,
  refreshIntervalMs: 500,
});

// The fetcher remains fully typed. After submitting the request,
// it'll poll until the activity reaches a terminal state.
try {
  const activity = await fetcher({
    body: {
      /* ... */
    },
  });

  // Success!
  console.log(activity.result.createPrivateKeysResult?.privateKeyIds?.[0]);
} catch (error) {
  if (error instanceof TurnkeyActivityError) {
    // In case the activity is rejected, failed, or requires consensus,
    // a rich `TurnkeyActivityError` will be thrown. You can read from
    // `TurnkeyActivityError` to find out why the activity didn't succeed.
    //
    // For instance, if your activity requires consensus and doesn't have
    // enough approvals, you can get the `activityId` from `TurnkeyActivityError`,
    // store it somewhere, then re-fetch the activity via `.postGetActivity(...)`
    // when the required approvals/rejections are in place.
  }
}

Note to reviewer

Feel free to review commit by commit (they are stacked). See changes in createNewEthereumPrivateKey.ts as a real word example.

How I Tested These Changes

• CI is green
• Ran the with-ethers example locally

[r-n-o]

Nice!!

[r-n-o]

❤️

[r-n-o]

🚢