Merge pull request #63 from MikeMcC399/add/ci-github-action

ci: add GitHub Actions workflow

.github/workflows/ci-test.yml

@@ -0,0 +1,24 @@
+name: ci-test
+on: [push, pull_request]
+
+jobs:
+
+  ps-tree-ci:
+    strategy:
+      fail-fast: false
+      matrix:
+        node: [18, 20, 22, 23]
+        os: [ubuntu-24.04, windows-2022, macos-14]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - name: Setup Node
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+      - run: node -v
+      - run: npm -v
+      - name: Checkout
+        uses: actions/checkout@v4
+      - run: npm ci
+      - run: npm test
+      - run: npm run coverage