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/random.py

@@ -1,10 +1,12 @@
 import contextlib
 import time
 from collections.abc import Callable, Generator, Sequence
-from typing import Any
+from typing import TypeVar
 
 RngState = tuple[float, float, float, int]
 
+T = TypeVar("T")
+
 _2_POW_32 = 0x100000000
 _2_POW_MINUS_32 = 2.3283064365386963e-10
 
@@ -102,11 +104,11 @@ def using(rng: Alea) -> Generator[None, None, None]:
         _current = previous
 
 
-def choice(source: Sequence[Any]) -> Any:
+def choice(source: Sequence[T]) -> T:
     return source[below(len(source))]
 
 
-def choice_low(source: Sequence[Any]) -> Any:
+def choice_low(source: Sequence[T]) -> T:
     return source[below_low(len(source))]