Turtle.Prelude.proc and Turtle.Prelude.shell don't pass keyboard input to ncurses programs.

I needed to press space bar on an ncurses program, but `proc` and `shell` couldn't do it.

I had to replace them with `import System.Process (spawnProcess, waitForProcess)`.

Below is how I use `spawnProcess` and `waitForProcess`.

```haskell
{-# LANGUAGE OverloadedStrings #-}
module TermdownAlarm where

import System.Process (spawnProcess, waitForProcess)
import Control.Monad (void)
import Data.Text (Text, unpack)
import Turtle (proc, empty)
import System.Exit (ExitCode(..))

termdownAlarm :: Text -> Text -> Text -> IO ()
termdownAlarm title duration file = do
exitCode <- spawnProcess "termdown"
[ "--alt-format", "--no-figlet"
, "--critical", "10", "--no-window-title", "--title"
, unpack title, unpack duration ] >>= waitForProcess
case exitCode of
ExitFailure _ -> return ()
ExitSuccess ->
void $ proc "mpv" ["--really-quiet", "--volume=100", file] empty
```

I can press space bar to pause and resume timer in `termdown` which is an ncurses program.

Start at Turtle.Prelude.proc and Turtle.Prelude.shell, then compare their behavior with System.Process.spawnProcess and waitForProcess shown in the report. Done means child ncurses programs receive keyboard input, including the space bar, when launched through proc or shell.

Written by the indexing model from the issue text.