Add sample build workflow

Author: xmlynek

.github/workflows/build-and-test.yaml

@@ -0,0 +1,71 @@
+name: Build and Test
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  backend-tests:
+    name: Backend - Build and Test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Set up JDK
+        uses: actions/setup-java@v3
+        with:
+          java-version: '23' # Update if using a different Java version
+          distribution: 'openjdk'
+
+      - name: Cache Maven dependencies
+        uses: actions/cache@v3
+        with:
+          path: ~/.m2
+          key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}
+          restore-keys: |
+            ${{ runner.os }}-maven-
+
+      - name: Build and test backend
+        run: |
+          cd backend
+          ./mvnw clean install
+
+  frontend-tests:
+    name: Frontend - Build and Test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v3
+        with:
+          node-version: '22'
+
+      - name: Cache npm dependencies
+        uses: actions/cache@v3
+        with:
+          path: ~/.npm
+          key: ${{ runner.os }}-node-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-node-
+
+      - name: Install dependencies
+        run: |
+          cd frontend
+          npm ci
+
+      - name: Run tests
+        run: |
+          npm run test -- --watch=false --no-progress
+
+      - name: Build frontend
+        run: |
+          npm run build -- --configuration production