ci: setup Node.js test execution for engine workspace (#79)

Author: fraxken

.github/workflows/workspace-engine.yml

@@ -0,0 +1,36 @@
+name: Mutex CI
+
+on:
+  push:
+    branches: [main]
+    paths:
+      - packages/engine/**
+  pull_request:
+    paths:
+      - packages/engine/**
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        node-version: [24.x]
+      fail-fast: false
+    steps:
+      - name: Harden Runner
+        uses: step-security/harden-runner@f4a75cfd619ee5ce8d5b864b0d183aff3c69b55a # v2.13.1
+        with:
+          egress-policy: audit
+
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5.0.0
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@a0853c24544627f65ddf259abe73b1d18a591444 # v5.0.0
+        with:
+          node-version: ${{ matrix.node-version }}
+      - name: Install dependencies
+        run: npm ci --ignore-scripts
+      - name: Run tests
+        run: npm run test --workspace=packages/engine