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/game_view/equipment_window.py

@@ -1,4 +1,4 @@
-from typing import Any
+import curses
 
 from pqcli.mechanic import EquipmentType, Player
 from pqcli.ui.curses.widgets import DataTable, Focusable, WindowWrapper
@@ -6,7 +6,13 @@ from pqcli.ui.curses.widgets import DataTable, Focusable, WindowWrapper
 
 class EquipmentWindow(Focusable, WindowWrapper):
     def __init__(
-        self, player: Player, parent: Any, h: int, w: int, y: int, x: int
+        self,
+        player: Player,
+        parent: curses.window,
+        h: int,
+        w: int,
+        y: int,
+        x: int,
     ) -> None:
         super().__init__(parent, h, w, y, x)
         self._on_focus_change += self._render