App, .cmds.Cmd: Add .distro property

DistroBase's option --id is now redundant to the new global option
--distro-id in the App class, so remove --id. The only added value
DistroBase then brings to the table is its .distro property, which
can be provided by App just fine at this point, given that App has
all it needs to construct a Distro object, so add .distro to App and
remove the entire DistroBase class.

For convenience, also make App.distro available as a newly added
cmds.Cmd.distro property. This also obviates the need for the
distro-related properties in the .distro.Cmd class, remove all that.

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

src/python/jw/pkg/App.py

@@ -5,7 +5,11 @@
 
 from __future__ import annotations
 
-from typing import TypeAlias
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from typing import TypeAlias
+    import os, sys, pwd, re
 
 import os, sys, argparse, pwd, re
 from functools import lru_cache
@@ -13,6 +17,7 @@ from enum import Enum, auto
 
 from .lib.App import App as Base
 from .lib.log import *
+from .lib.Distro import Distro
 
 # Meaning of pkg.requires.xxx variables
 # build: needs to be built and installed before this can be built
@@ -218,6 +223,7 @@ class App(Base):
         self.__distro_id: str|None = None
         self.__distro_name: str|None = None
         self.__distro_codename: str|None = None
+        self.__distro: Distro|None = None
         self.__os_cascade: list[str]|None = None
         self.__res_cache = ResultCache()
         self.__topdir: str|None = None
@@ -380,6 +386,13 @@ class App(Base):
 
         raise RuntimeError('Failed to get GNU triplet from running machine')
 
+    @property
+    def distro(self) -> Distro:
+        if self.__distro is None:
+            ret = Distro.instantiate(self.distro_id, ec=self.exec_context)
+            self.__distro = ret
+        return self.__distro
+
     def find_dir(self, name: str, search_subdirs: list[str]=[], search_absdirs: list[str]=[], pretty: bool=True):
         return self.__find_dir(name, search_subdirs, search_absdirs, pretty)