lib.{App,Cmd}: Pass parent= by name to Cmd* constructors

The framework instantiates command classes in two places: the top-level
commands in App and the lazily materialized subcommands in
Cmd.add_subcommands(). Both pass the parent parameter positionally.

Change that to passing parent by keyword at both call sites. Every command
class names its first __init__() parameter parent, so the keyword form
binds the same slot for all of them regardless of parameter order, and it
allows a command class to declare parent as keyword-only.

Signed-off-by: Jan Lindemann <jan@janware.com>

src/python/jw/pkg/lib/App.py

@@ -220,7 +220,7 @@ class App:  # export
                 type_name_filter = name_filter,
                 type_filter = [AbstractCmd],
             )
-            self.__cmds = [cmd_class(self) for cmd_class in cmd_classes]
+            self.__cmds = [cmd_class(parent = self) for cmd_class in cmd_classes]
         self._build_parser()
 
     def _build_parser(self, argv: list[str] | None = None) -> None:

src/python/jw/pkg/lib/Cmd.py

@@ -126,7 +126,7 @@ class AbstractCmd(abc.ABC):
                     if cmd_class in self.__child_classes:
                         continue
                     self.__child_classes.append(cmd_class)
-                    cmd = cmd_class(self)
+                    cmd = cmd_class(parent = self)
                     self.__children.append(cmd)
                     assert len(self.__children) == len(self.__child_classes)
             except Exception as e: