Add Hello World implementation of Idle scene

from dataclasses import dataclass

from typing import cast

from poolpay.display.PygameDisplay import PygameDisplay

from poolpay.ui.scenes.Idle import Idle as IdleBase

@dataclass(frozen=True)

class Idle(IdleBase):

    def present(self) -> None:

        # TODO Add actual UI

        pygame.font.init()

        defaultFont = pygame.font.SysFont(None, 30)

        display = cast(PygameDisplay, self.director.display)

        display.surface.fill((128, 128, 128))

        display.surface.blit(

            defaultFont.render("Hello World!", False, (0, 0, 0)), (0, 0)

        )

        display.refresh()