huge refactor of plugin system

cmdnat/__init__.py

@@ -28,15 +28,20 @@ def _register_cmdlet_object(cmdlet_obj, registry: Dict[str, CmdletFn]) -> None:
         registry[alias.replace("_", "-").lower()] = run_fn
 
 
-def register_native_commands(registry: Dict[str, CmdletFn]) -> None:
-    """Import native command modules and register their CMDLET exec functions."""
+def _iter_legacy_native_module_names() -> list[str]:
     base_dir = os.path.dirname(__file__)
+    module_names: list[str] = []
     for filename in os.listdir(base_dir):
         if not (filename.endswith(".py") and not filename.startswith("_")
                 and filename != "__init__.py"):
             continue
+        module_names.append(filename[:-3])
+    return module_names
 
-        mod_name = filename[:-3]
+
+def register_native_commands(registry: Dict[str, CmdletFn]) -> None:
+    """Import legacy local command modules from cmdnat/ and register them."""
+    for mod_name in _iter_legacy_native_module_names():
         try:
             module = import_module(f".{mod_name}", __name__)
             cmdlet_obj = getattr(module, "CMDLET", None)