ci: streamline docs workflows, migrate scripts to ci/scripts and update www image

ci/scripts/setup-env.sh

@@ -0,0 +1,35 @@
+#!/bin/bash
+set -euo pipefail
+
+PNPM_VERSION="${1:-9.12.3}"
+NODE_VERSION="${2:-20}"
+
+# Configure pnpm
+case "$PNPM_VERSION" in
+  8|9|9.12.3) ;;
+  *) echo "Unsupported pnpm version: $PNPM_VERSION" >&2; exit 1 ;;
+esac
+
+PNPM_BIN="/opt/ci/pnpm/$PNPM_VERSION/bin"
+if [ -d "$PNPM_BIN" ]; then
+  if [ -n "${GITHUB_PATH:-}" ]; then
+    echo "$PNPM_BIN" >> "$GITHUB_PATH"
+  fi
+  export PATH="$PNPM_BIN:$PATH"
+fi
+
+# Configure Node.js
+case "$NODE_VERSION" in
+  18*) major=18 ;;
+  20*) major=20 ;;
+  22*) major=22 ;;
+  *) echo "Unsupported node version: $NODE_VERSION" >&2; exit 1 ;;
+esac
+
+NODE_BIN="/opt/ci/node/$major/bin"
+if [ -d "$NODE_BIN" ]; then
+  if [ -n "${GITHUB_PATH:-}" ]; then
+    echo "$NODE_BIN" >> "$GITHUB_PATH"
+  fi
+  export PATH="$NODE_BIN:$PATH"
+fi