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/util.py

@@ -2,7 +2,7 @@ import curses
 import curses.ascii
 from collections.abc import Callable, Iterable
 from dataclasses import dataclass
-from typing import Any, TypeVar, overload
+from typing import TypeVar, overload
 
 KEYS_CYCLE = {curses.ascii.TAB}
 KEYS_DOWN = set(map(ord, "jJ")) | {curses.KEY_DOWN}
@@ -16,7 +16,7 @@ KEYS_CANCEL = set(map(ord, "qQ")) | {curses.ascii.ESC}
 class Choice:
     keys: list[int]
     desc: str
-    callback: Callable[..., Any]
+    callback: Callable[[], object]
 
 
 ItemT = TypeVar("ItemT")
@@ -31,5 +31,7 @@ def first(source: Iterable[ItemT]) -> ItemT | None: ...
 def first(source: Iterable[ItemT], default: DefaultT) -> ItemT | DefaultT: ...
 
 
-def first(source: Iterable[Any], default: Any = None) -> Any:
+def first(
+    source: Iterable[ItemT], default: DefaultT | None = None
+) -> ItemT | DefaultT | None:
     return next(iter(source), default)