feat: add Docker CI/CD workflow for automated builds

Introduced a new Forgejo Actions workflow to automate the Docker image build and push process on tag creation. The workflow sets up the environment, including QEMU and Buildx, logs into Docker Hub, and pushes the built image. This improvement ensures consistent and efficient Docker image deployment.

.forgejo/workflows/docker.yml

@@ -0,0 +1,33 @@
+name: Docker CI/CD
+
+on:
+  push:
+    tags:
+      - "*"
+
+jobs:
+  docker:
+    name: Docker Build and Push to Docker Hub
+    container:
+      image: node:20-bookworm
+    steps:
+      - name: Install dependencies
+        run: |
+          apt update
+          apt install -y docker.io
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Build and push to Docker Hub
+        uses: docker/build-push-action@v5
+        with:
+          push: true
+          tags: |
+            privatecoffee/structables:latest
+            privatecoffee/structables:${{ env.GITHUB_REF_NAME }}