fix: tool: disinto backup import — idempotent restore on fresh Nomad cluster (#1058)

lib/disinto/backup.sh

@@ -310,9 +310,15 @@ backup_import_issues() {
 backup_import() {
   local tarball="$1"
 
-  # Validate required environment
-  [ -n "${FORGE_URL:-}" ] || { echo "Error: FORGE_URL not set" >&2; exit 1; }
-  [ -n "${FORGE_TOKEN:-}" ] || { echo "Error: FORGE_TOKEN not set" >&2; exit 1; }
+  if [ -z "${FORGE_URL:-}" ]; then
+    echo "Error: FORGE_URL not set" >&2
+    exit 1
+  fi
+
+  if [ -z "${FORGE_TOKEN:-}" ]; then
+    echo "Error: FORGE_TOKEN not set" >&2
+    exit 1
+  fi
 
   backup_log "=== Backup Import Started ==="
   backup_log "Target: ${FORGE_URL}"