ci: add GitHub Actions test workflow

.github/workflows/ci.yml

@@ -0,0 +1,46 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  backend:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '21'
+          cache: maven
+
+      - name: Run Maven tests
+        run: mvn -B test
+
+  web-ui:
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: web-ui
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: npm
+          cache-dependency-path: web-ui/package-lock.json
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run Web UI tests
+        run: npm run test:ci

.gitignore

@@ -63,6 +63,7 @@ web-ui/*
 !web-ui/test/
 !web-ui/index.html
 !web-ui/package.json
+!web-ui/package-lock.json
 !web-ui/demo-*.html
 !web-ui/e2e/
 !web-ui/playwright.config.ts