Adds the audit.forwarders config list and a Sink interface with three
implementations: stdout, RFC 5424 syslog over UDP/TCP (hand-rolled —
stdlib log/syslog only emits RFC 3164 and does not build on Windows),
and webhook POSTs through the SSRF-safe HTTP client. Forwarders are
best-effort fan-out: the local file stays the source of truth and a
dead sink is logged instead of poison-queueing every event.
kolaente