Add per-route details to status, move socket to /srv/mc-proxy/

mcproxyctl status now shows individual routes per listener with
hostname, backend, mode, and re-encrypt indicator. Proto, gRPC
server, client library, and CLI all updated.

Default gRPC socket path moved from /var/run/mc-proxy.sock to
/srv/mc-proxy/mc-proxy.sock to match the service data directory
convention.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

cmd/mcproxyctl/status.go

@@ -34,6 +34,17 @@ func statusCmd() *cobra.Command {
 
 			for _, ls := range status.Listeners {
 				fmt.Printf("  %s  routes=%d  active=%d\n", ls.Addr, ls.RouteCount, ls.ActiveConnections)
+				for _, r := range ls.Routes {
+					mode := r.Mode
+					if mode == "" {
+						mode = "l4"
+					}
+					extra := ""
+					if r.BackendTLS {
+						extra = " (re-encrypt)"
+					}
+					fmt.Printf("    %s %s → %s%s\n", mode, r.Hostname, r.Backend, extra)
+				}
 			}
 
 			return nil