ci: add Node.js test & automerge for dependabot

Author: fraxken

.github/workflows/node.js.yml

@@ -0,0 +1,52 @@
+name: Node.js CI
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ${{matrix.os}}
+    strategy:
+      matrix:
+        node-version: [20.x, 22.x]
+        os: [ubuntu-latest, windows-latest, macos-latest]
+      fail-fast: false
+    steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@0634a2670c59f64b4a01f0f96f84700a4088b9f0 # v2.12.0
+        with:
+          egress-policy: audit
+
+      - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4.4.0
+        with:
+          node-version: ${{ matrix.node-version }}
+      - name: Install dependencies
+        run: npm i
+      - name: Build
+        run: npm run build
+      - name: Lint
+        run: npm run lint
+      - name: Run tests
+        run: npm run test
+  automerge:
+    if: >
+      github.event_name == 'pull_request' && github.event.pull_request.user.login == 'dependabot[bot]'
+    needs:
+      - test
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+    steps:
+      - name: Merge Dependabot PR
+        uses: fastify/github-action-merge-dependabot@e820d631adb1d8ab16c3b93e5afe713450884a4a # v3.11.1
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}