Inconsistent imports styles in `Lib/_pyrepl`

[donbarbos]

Bug report

Bug description:

After this PR #111567 there were still some strange imports in Lib/_pyrepl, for example:

cpython/Lib/_pyrepl/_threading_handler.py

Lines 7 to 11 in 4e3330f

	TYPE_CHECKING = False
	if TYPE_CHECKING:
	from threading import Thread
	from types import TracebackType
	from typing import Protocol

cpython/Lib/_pyrepl/commands.py

Lines 35 to 37 in 4e3330f

	# types
	if False:
	from .historical_reader import HistoricalReader

cpython/Lib/_pyrepl/completing_reader.py

Lines 30 to 33 in 4e3330f

	# types
	Command = commands.Command
	if False:
	from .types import KeySpec, CommandName

I just want to send a PR with a uniform style and understandable for everyone.
moreover, there are imports of types that are not put in the if block, although they are used only for type hinting.

There is also a warning import twice, global import and lazy import in Lib/_pyrepl/readline.py

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-129758: Correct imports in Lib/_pyrepl #129761