Add automatic Docker build for "develop" tag

.github/workflows/docker-develop.yml

@@ -0,0 +1,46 @@
+name: Build and Push Docker Image (develop)
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+    inputs:
+      image_tag:
+        description: 'Docker image tag'
+        required: false
+        default: 'develop'
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          distribution: 'temurin'
+          java-version: '21'
+
+      - name: Run production build
+        run: ./gradlew clean build -Pvaadin.productionMode=true
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: docker/Dockerfile
+          platforms: linux/arm64/v8,linux/amd64
+          push: true
+          tags: grimsi/gameyfin:${{ inputs.image_tag || 'develop' }}