Added various NPM scripts.

npm/npm-install/action.yaml

@@ -0,0 +1,36 @@
+name: npm-install
+description: "Download the desired NPM package tarball."
+inputs:
+  name:
+    description: "Name of the package."
+    required: true
+  version:
+    description: "Version of the package."
+    required: false
+    default: ""
+  prerelease:
+    description: "Install prerelease packages. Values: true, false."
+    required: false
+    default: "false"
+  outputDirectory:
+    description: "Directory for the output file."
+    required: true
+    default: "."
+  registry:
+    description: "NPM registry URL."
+    required: false
+    default: "https://npm.pkg.github.com"
+  authToken:
+    description: "Authentication token for the registry."
+    required: true
+outputs:
+  tgz:
+    description: "The path to the .tgz file."
+    value: ${{ steps.download.outputs.tgz }}
+runs:
+  using: "composite"
+  steps:
+  - name: "Download the package."
+    id: download
+    run: bash ${{ github.action_path }}/download_package.sh "${{ inputs.name }}" "${{ inputs.version }}" "${{ inputs.registry }}" "${{ inputs.authToken }}" "${{ inputs.outputDirectory }}"
+    shell: bash

npm/npm-install/download_package.sh

@@ -0,0 +1,65 @@
+#!/bin/bash
+set -e
+
+PACKAGE_NAME="$1"
+VERSION="$2"
+REGISTRY="$3"
+AUTH_TOKEN="$4"
+OUTPUT_DIR="${5:-.}"
+
+if [[ ! -f "$GITHUB_OUTPUT" ]]; then
+    GITHUB_OUTPUT="/dev/fd/1"
+fi
+
+# Ensure version is provided
+if [[ -z "$VERSION" ]]; then
+    echo "Error: VERSION is required"
+    exit 1
+fi
+
+# Download the tarball
+TARBALL_URL="$REGISTRY/$PACKAGE_NAME/-/$PACKAGE_NAME-$VERSION.tgz"
+TGZ_NAME="$PACKAGE_NAME-$VERSION.tgz"
+mkdir -p "$OUTPUT_DIR"
+TGZ_PATH="$OUTPUT_DIR/$TGZ_NAME"
+
+echo "Downloading $TARBALL_URL"
+CURL_HEADERS=()
+if [[ -n "$AUTH_TOKEN" ]]; then
+    CURL_HEADERS+=(-H "Authorization: Bearer $AUTH_TOKEN")
+fi
+
+# Download and capture HTTP status separately
+# Temporarily disable 'exit on error' to capture status
+set +e
+HTTP_CODE=$(curl -sL -w "%{http_code}" -o "$TGZ_PATH" "${CURL_HEADERS[@]}" "$TARBALL_URL")
+CURL_EXIT=$?
+set -e
+
+# Check if curl command itself failed (network issues, DNS, etc)
+if [[ $CURL_EXIT -ne 0 ]]; then
+    echo "Error: curl failed with exit code $CURL_EXIT (network error or invalid URL)"
+    rm -f "$TGZ_PATH"
+    exit 1
+fi
+
+# Check HTTP status code
+if [[ "$HTTP_CODE" != "200" ]]; then
+    echo "Error: Failed to download package (HTTP $HTTP_CODE)"
+    if [[ -f "$TGZ_PATH" ]]; then
+        echo "Response preview:"
+        head -c 500 "$TGZ_PATH"
+        echo ""
+        rm -f "$TGZ_PATH"
+    fi
+    exit 1
+fi
+
+if [[ ! -f "$TGZ_PATH" ]]; then
+    echo "Error: Download failed - file not created"
+    exit 1
+fi
+
+echo "tgz=$TGZ_PATH" >> "$GITHUB_OUTPUT"
+
+echo "Downloaded $TGZ_NAME"