Fix Google Vertex production ADC mode support by routing explicit google-vertex models to the Vertex transport and relying on google-auth-library for request-time ADC resolution.
Verification:
- pnpm install --frozen-lockfile
- pnpm test extensions/google/transport-stream.test.ts extensions/google/index.test.ts src/config/zod-schema.models.test.ts src/agents/pi-embedded-runner/model.inline-provider.test.ts -- --reporter=verbose
- pnpm check:changed
- GitHub PR checks green on c4b7cad4df
- Live ADC smoke reached Google Vertex auth/transport and failed only because the configured redacted project has the Vertex AI API disabled
Co-authored-by: Damian Finol <damian@felixpago.com>