refactor(download): remove ProviderCore/download.py, move sanitize_filename to SYS.utils, replace callers to use API.HTTP.HTTPClient

cmdlet/_shared.py

@@ -219,17 +219,18 @@ class SharedArgs:
                 SharedArgs.STORE.choices = SharedArgs.get_store_choices(config)
         """
         try:
-            from Store import Store
+            # Use the non-instantiating helper so autocomplete doesn't trigger backend init.
+            from Store.registry import list_configured_backend_names
 
             # If no config provided, try to load it
             if config is None:
                 try:
                     from SYS.config import load_config
+                    config = load_config()
                 except Exception:
                     return []
 
-            store = Store(config)
-            return store.list_backends()
+            return list_configured_backend_names(config)
         except Exception:
             # Fallback to empty list if FileStorage isn't available
             return []