### Added

- GitHub Actions CI across Node.js 18, 20, 22, and 24 against the packed npm artifact
- GitHub Actions publish workflow on release with npm trusted publishing
- `prepack` script to build distributions before `npm pack` / `npm publish`

### Changed
- Replace Travis CI with GitHub Actions
- Update README badges to GitHub Actions, npm, and jsDelivr
- Upgrade mocha and pin vulnerable transitive dependencies via npm overrides

.github/workflows/ci.yml

@@ -0,0 +1,77 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+      branches:
+        - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Node 24
+        uses: actions/setup-node@v4
+        with:
+          node-version: 24.x
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Pack npm package
+        run: |
+          mkdir -p package-artifact
+          npm pack --pack-destination package-artifact
+
+      - name: Upload package artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: package-node-24
+          path: package-artifact/*.tgz
+          if-no-files-found: error
+
+  runtime-test:
+    needs: build
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [18.x, 20.x, 22.x, 24.x]
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Node ${{ matrix.node-version }}
+        uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node-version }}
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Download package artifact
+        uses: actions/download-artifact@v4
+        with:
+          name: package-node-24
+          path: package-artifact
+
+      - name: Extract package artifact
+        run: tar -xzf package-artifact/*.tgz --strip-components=1 -C .
+
+      - name: Run runtime tests
+        if: matrix.node-version != '24.x'
+        run: npm run test:runtime
+
+      - name: Run runtime tests with coverage
+        if: matrix.node-version == '24.x'
+        run: npm run test:coverage
+
+      - name: Upload to coveralls
+        if: matrix.node-version == '24.x'
+        uses: coverallsapp/github-action@v2
+        with:
+          file: ./coverage/lcov.info