pyproject.toml: Enforce import annotations style

Add new ruff rules and fix their fallout:

  future-annotations = true

   select = [
    "TC",  # type-checking import placement rules
    "FA",  # future annotations rules
   ]

This comprises:

  - Streamline imports and exports in cmds.xxx.Cmd

    - Import base class as "Base"

    - Export types Cmd and Parent via __all__

  - Move all types imported only for annotation below TYPE_CHECKING

  - Use "from __future__ import annotations" all over the place

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

src/python/jw/pkg/cmds/projects/CmdBuild.py

@@ -1,14 +1,18 @@
+from __future__ import annotations
 import datetime
 import os
 import re
 
-from argparse import ArgumentParser, Namespace
 from functools import lru_cache
 
 from ...App import Scope
 from ...lib.log import DEBUG, ERR, NOTICE, log
 from ...lib.util import get_profile_env, pretty_cmd
 from .Cmd import Cmd, Parent
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from argparse import ArgumentParser, Namespace
 
 class CmdBuild(Cmd):  # export