internal/ai/llm defines the single Provider interface (Generate,
ListModels, Verify) shared by every vendor adapter, with Request,
Message, JSONSchema, Response, Usage and Model types.
Typed errors work with errors.Is/As: sentinels ErrAuth, ErrTimeout and
ErrBadOutput; *RateLimitedError (RetryAfter) matching ErrRateLimited;
*ProviderError (status and body excerpt) matching ErrProvider.
NewProviderError redacts every given secret before truncating the body,
so no part of an API key reaches an error string.
Fake is a thread-safe scripted Provider for tests: it returns queued
results in order, fails unscripted calls, and records deep copies of
every Request.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
