fix: refuse a missing emulator profile directory

scripts/fileless_audit.py

@@ -25,7 +25,7 @@ from pathlib import Path
 sys.path.insert(0, os.path.dirname(__file__))
 
 import upstream
-from common import suggest_names
+from common import require_directory, suggest_names
 from profile_sync import collect_citations, ref_role, select_views, split_source_ref
 from safeparse import yaml_load
 
@@ -122,6 +122,7 @@ def main() -> None:
     args = parser.parse_args()
     if args.all == bool(args.emulators):
         parser.error("name profiles or pass --all, not both")
+    require_directory(args.emulators_dir, "--emulators-dir")
 
     known = sorted(path.stem for path in Path(args.emulators_dir).glob("*.yml"))
     unknown = [name for name in args.emulators if name not in known]