misc: replace Any with precise types

Curses screens, windows and pads are typed as curses.window, and the
widgets that may get no parent window take curses.window | None.

- EventHandler is generic over a ParamSpec, so each handler declares
  the arguments it passes, and MenuView is generic over the item its
  on_confirm hands out. Choice callbacks take no arguments.
- Scrollable is generic over its items, which DataTable and ListBox
  fix to tuple[str, str] and str.
- random.choice() and choice_low() are generic over the sequence, so
  the casts at their call sites are gone. BasicUserInterface.menu()
  and util.first() are generic too.
- Signal callbacks and their payloads are Callable[..., object] and
  object, since emit() only forwards them.
- JSON values in game_data are object and narrowed by isinstance,
  and data files are Traversable.
- Signal handlers take an int and a FrameType | None, and
  list_players() takes a TextIO.
- The focus_standout() context managers return
  Generator[None, None, None].

Any remains in three places: Player.__setstate__, whose pickled
__dict__ holds values of every type; Focusable.__init__, a mixin that
passes *args and **kwargs through to the next class; and the values
load_game_data() collects, whose element type depends on the field
each one fills.

pqcli/ui/curses/__init__.py

@@ -3,7 +3,7 @@ import curses
 import os
 import signal
 import time
-from typing import Any
+from types import FrameType
 
 from pqcli import lingo
 from pqcli.config import Class, Race
@@ -68,7 +68,7 @@ class CursesUserInterface(BaseUserInterface):
             curses.init_pair(COLOR_PROGRESSBAR, 0, 9)
             curses.init_pair(COLOR_HIGHLIGHT, 3, -1)
 
-        def signal_handler(sig: Any, frame: Any) -> None:
+        def signal_handler(sig: int, frame: FrameType | None) -> None:
             if self.args.use_saves:
                 self.roster.save()
             exit(0)