Expand description
On-disk client config: ~/.cinch/config.json.
Wire-compatible with the Go CLI’s cinch/internal/config/config.go schema.
MultiConfig is the canonical disk format; Config is the legacy single-relay
shape kept for backwards compatibility (and as the in-memory shape consumers
handle most often via MultiConfig::to_active_config).
Permissions: 0700 dir, 0600 file on Unix.