fix: limit yq Go thread usage on hosts with low ulimit -u

IONOS shared hosting enforces a strict process limit. yq (a Go binary)
tries to spawn several OS threads at startup and crashes with
"failed to create new OS thread (errno=11 EAGAIN)" when the limit is
hit, returning empty stdout. This silently skips all references.

Wrap yq with GOMAXPROCS=1 GOGC=off so the Go runtime uses a single
goroutine-running thread and skips GC goroutines, staying within the
host's ulimit -u.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

scripts/arty.sh

@@ -163,6 +163,11 @@ load_env_vars() {
   fi
 }
 
+# Wrapper to limit Go thread usage on hosts with low ulimit -u (e.g. IONOS shared hosting)
+yq() {
+  GOMAXPROCS=1 GOGC=off command yq "$@"
+}
+
 # Check if yq is installed
 check_yq() {
   if ! command -v yq &>/dev/null; then