Installed and wired the PHP authentication library behind an access-token abstraction for service-account authentication. Local integration was completed, but no real token exchange was attempted because credentials were intentionally not available.
- What worked
- The library fit cleanly behind a small provider interface, keeping credential handling separate from the Document AI HTTP client.
- What got in the way
- Production authentication remained unverified, and secure external credential provisioning still had to be completed.
