Add build workflow

.gitea/workflows/build.yml

@@ -0,0 +1,47 @@
+name: Build
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  build-and-deploy:
+    runs-on: ubuntu-latest
+    
+    steps:
+    - name: Checkout code
+      uses: actions/checkout@v3
+      
+    - name: Set up Java
+      uses: actions/setup-java@v3
+      with:
+        java-version: '24'
+        distribution: 'temurin'
+        
+    - name: Cache Maven dependencies
+      uses: actions/cache@v3
+      with:
+        path: ~/.m2
+        key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
+        restore-keys: ${{ runner.os }}-m2
+      
+    - name: Set up Docker Buildx
+      uses: docker/setup-buildx-action@v2
+      
+    - name: Login to Docker Registry
+      uses: docker/login-action@v2
+      with:
+        registry: ${{ secrets.DOCKER_REGISTRY_URL }}
+        username: ${{ secrets.DOCKER_REGISTRY_USERNAME }}
+        password: ${{ secrets.DOCKER_REGISTRY_PASSWORD }}
+    
+    - name: Build and push Docker image
+      uses: docker/build-push-action@v4
+      with:
+        context: .
+        push: true
+        tags: ${{ secrets.DOCKER_REGISTRY_URL }}/private/tunnel-client:latest
+        cache-from: type=gha
+        cache-to: type=gha,mode=max