Incorporate OAuth retry logic from conformance helpers into SDK

[bhosmer-ant]

Context

In PR #1360 (client conformance testing), there's a TODO comment in src/conformance/helpers/withOAuthRetry.ts:30-31:

// TODO: this retry logic should be incorporated into the typescript SDK

The conformance test helper implements OAuth retry logic that:

1. Handles 401/403 responses by attempting re-authentication
2. Extracts resourceMetadataUrl and scope from WWW-Authenticate headers
3. Automatically retries the request after obtaining fresh tokens
4. Handles the authorization code flow including redirect handling

Suggestion

Consider incorporating this retry pattern into the SDK's withOAuth middleware or as a separate utility, so SDK users don't need to implement this logic themselves.

Related

• PR feat: add client conformance testing #1360: feat: add client conformance testing