build linux wheels with manylinux_2_28 for wider glibc compat (#18)

* build linux wheels inside manylinux_2_28 for glibc 2.28 compat

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* add perl-IPC-Cmd for openssl build in manylinux

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

build_wheels.sh

@@ -0,0 +1,33 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+cd "$DIR"
+
+WHEEL_DIR="${1:-dist}"
+
+# on Linux, build inside manylinux_2_28 container for glibc 2.28 compatibility.
+# for reference, Ubuntu 20.04 is glibc 2.31, so this gives us wide compatibility.
+if [ "$(uname)" = "Linux" ] && [ -z "${MANYLINUX:-}" ]; then
+  ARCH="$(uname -m)"
+  IMAGE="quay.io/pypa/manylinux_2_28_${ARCH}"
+  exec docker run --rm \
+    -e MANYLINUX=1 \
+    -v "$DIR:/work" \
+    -w /work \
+    "$IMAGE" \
+    bash build_wheels.sh "$WHEEL_DIR"
+fi
+
+# Set up Python inside manylinux container
+if [ -n "${MANYLINUX:-}" ]; then
+  export PATH="/opt/python/cp312-cp312/bin:$PATH"
+fi
+
+./setup.sh
+pip install setuptools wheel
+
+mkdir -p "$WHEEL_DIR"
+for pkg in */pyproject.toml; do
+  pip wheel "./$(dirname "$pkg")" --no-deps --wheel-dir "$WHEEL_DIR"/
+done