feat: add GitHub Actions workflow for building and pushing Docker image

Author: andrenormanlang

.github/workflows/docker-hub.yml

@@ -0,0 +1,34 @@
+name: Build & Push API Docker Image
+
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build-and-push:
+    runs-on: ubuntu-latest
+    if: github.ref == 'refs/heads/main'
+
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - 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: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: docker/Dockerfile
+          push: true
+          tags: |
+            andrenormanlang/mindsmesh-api:latest
+            andrenormanlang/mindsmesh-api:${{ github.sha }}