Python resolves the Vertex project and location as call params, then the
litellm.vertex_project / litellm.vertex_location globals, then env, and
Azure AD token refresh from litellm.enable_azure_ad_token_refresh alone.
Native OCR skipped the globals, so a config.yaml litellm_settings value
silently fell through to the credential's project and us-central1, and a
managed identity setup without an API key failed. The bridge now reads
them through a provider_defaults settings group into OcrSettings, and
VertexConfig / AzureAuthInputs slot them in at Python's precedence.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>