Wire gorilla/websocket into the Go companion agent to send arbitrary
console commands (e.g. oxide.reload BetterLoot) to the Rust Dedicated
Server's WebRCON endpoint. Adds RCON_PORT and RCON_PASSWORD env vars,
a new "command" action on the existing cmd.server NATS subject, and
the internal/rcon package that handles the JSON-over-WebSocket protocol.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
