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/views/menu_view.py

@@ -1,19 +1,22 @@
-from typing import Any
+import curses
+from typing import Generic, TypeVar
 
 from pqcli.ui.curses.event_handler import EventHandler
 from pqcli.ui.curses.util import Choice
 from pqcli.ui.curses.views.base_view import BaseView
 from pqcli.ui.curses.widgets import Menu
 
+ItemT = TypeVar("ItemT")
 
-class MenuView(BaseView):
+
+class MenuView(BaseView, Generic[ItemT]):
     def __init__(
-        self, screen: Any, title: str, active_choice: int = 0
+        self, screen: curses.window, title: str, active_choice: int = 0
     ) -> None:
         super().__init__(screen)
 
-        self.on_cancel = EventHandler()
-        self.on_confirm = EventHandler()
+        self.on_cancel = EventHandler[[]]()
+        self.on_confirm = EventHandler[[ItemT]]()
 
         self._title = f"{title}:"
         self._choices: list[Choice] = []