The audit logger is opened at startup (exit 2 on failure) and obtained before
every call, which is refused with audit_unavailable otherwise. Audit records only
take validated path and sudo values and use the request id as correlation id. The
rate limiter evicts idle keys, caps tracked keys, audits the first excess per key
and window and uses the settings passed to the app. FORWARDED_ALLOW_IPS is now a
setting, and startup warns about a missing host allow-list and unavailable OAuth.
Low-level SDK server built from the catalog plus gitea_api_request, with TOOLSETS/READ_ONLY/DISABLED_TOOLS filters, schema validation without value echo, one audit event per call, static bearer verifier, identity resolver hook, /health, DNS-rebinding protection, rate limiting and fail-closed startup checks.