Register anthropic_compatible in the provider registry so its env config,
modalities, test model, and /api/providers entry are derived from PROVIDERS
(#1075's single source of truth); the only manual copy is the SupportedProvider
Literal. Maps to esperanto's anthropic provider with a custom base_url, and
re-injects that base_url via ChatAnthropic since esperanto's to_langchain drops
it. Connection-test and model discovery mirror the openai_compatible siblings,
including DNS-rebinding pinning (prepare_pinned_http_target). A single shared
validator enforces the base_url + api_key requirement on both the create and
update paths.
Co-authored-by: Matt Van Horn <455140+mvanhorn@users.noreply.github.com>
Co-authored-by: Luis Novo <lfnovo@gmail.com>
Matt Van Horn
95a6453009