Feature: Add guide to install system dependencies with pixi

Describe the enhancement or feature you would like

I've stopped using brew on my macOS and I'm instead using pixi whenever I need system-level dependencies. This works very well in practice even for building CPython and I can do things like pixi run configure and it automatically sets up all of the system dependencies and runs configure. Doing that requires setting some environment variables here and there, but I've done that in a pixi.toml and it's all automated. It looks somewhat like this:

[project]
name = "cpython-dev"
channels = ["conda-forge"]
platforms = ["osx-arm64"]

[dependencies]
gdbm = "*"
libmpdec-devel = "*"
openssl = "3.*"
pkg-config = "*"
tk = "*"
xz = "*"
zstd = "*"
zlib = "*"

[tasks.configure]
cmd = "./configure --with-openssl=$CONDA_PREFIX"

[tasks.configure.env]
PKG_CONFIG_PATH = "$CONDA_PREFIX/lib/pkgconfig"
GDBM_CFLAGS = "-I$CONDA_PREFIX/include"
GDBM_LIBS = "-L$CONDA_PREFIX/lib -lgdbm"
TCLTK_CFLAGS = "$(pkg-config --cflags tcl tk)"
# tcl.pc and tk.pc files contain stub libraries, but those do not extist
# in the conda package
TCLTK_LIBS = "$(pkg-config --libs tcl tk | sed 's/-l[^ ]*stub[^ ]*//g')"
LDFLAGS = "-Wl,-rpath,$CONDA_PREFIX/lib"

It's a bit too much to propose adding this to the CPython repo, at least for now. However, pointing to this as a way to install system-level dependencies in the devguide doesn't sounds like a bad idea to me.

Thoughts? Is there an appetite for this? If so, I can start drafting a PR.

Describe alternatives you have considered

No response

Additional context

No response

まず、システムレベルの依存関係のインストールに関する devguide の既存のガイダンスを確認し、提案されている pixi.toml ワークフローと比較します。Issue に示されている依存関係と環境設定を網羅する、簡潔な pixi ベースの選択肢またはリンクを追加し、その後、開発環境のセットアップ手順が完全で理解しやすいことを確認します。