feat: add merge workflow

.github/workflows/merge.yml

@@ -0,0 +1,78 @@
+name: Build and Push Docker Image On Merge
+
+on:
+  push:
+    branches: ['main']
+  workflow_dispatch:
+
+jobs:
+  paths-filter:
+    runs-on: ubuntu-latest
+    outputs:
+      frontend: ${{ steps.filter.outputs.frontend }}
+      api: ${{ steps.filter.outputs.api }}
+      widget: ${{ steps.filter.outputs.widget }}
+    steps:
+      - uses: actions/checkout@v4
+      - name: Filter paths
+        id: filter
+        uses: dorny/paths-filter@v3
+        with:
+          filters: |
+            frontend:
+              - 'frontend/**'
+            api:
+              - 'api/**'
+            widget:
+              - 'widget/**'
+
+  build-and-push:
+    runs-on: ubuntu-latest
+    needs:
+      - paths-filter
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+
+      - 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
+        id: docker_login
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Build and push frontend Docker image
+        if: ${{ needs.paths-filter.outputs.frontend == 'true' }}
+        uses: docker/build-push-action@v6
+        with:
+          context: ./
+          file: ./frontend/Dockerfile
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ secrets.DOCKERHUB_USERNAME }}/hexabot-frontend:latest
+
+      - name: Build and push API Docker image
+        if: ${{ needs.paths-filter.outputs.api == 'true' }}
+        uses: docker/build-push-action@v6
+        with:
+          context: ./
+          file: ./api/Dockerfile
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ secrets.DOCKERHUB_USERNAME }}/hexabot-api:latest
+
+      - name: Build and push widget Docker image
+        if: ${{ needs.paths-filter.outputs.widget == 'true' }}
+        uses: docker/build-push-action@v6
+        with:
+          context: ./
+          file: ./widget/Dockerfile
+          platforms: linux/amd64,linux/arm64
+          push: true
+          tags: ${{ secrets.DOCKERHUB_USERNAME }}/hexabot-widget:latest