Preserve LF stdin output on Windows

[AleksZyro]

Refs #2453.

When sorting stdin to stdout on Windows, Python's text-mode stdout can translate \n to \r\n. That makes LF input become CRLF output even when isort inferred LF from the input stream.

This writes stdin sorting output through a stdout wrapper with newline translation disabled, and adds a regression test for LF input written through a text stdout stream.

Tested with:

python -m pytest tests/unit/test_main.py::test_isort_with_stdin_preserves_lf_stdout -q
python -m pytest tests/unit/test_main.py::test_isort_with_stdin -q
python -m ruff check isort/main.py tests/unit/test_main.py
python -m ruff format --check isort/main.py tests/unit/test_main.py