Add builder workflow

.github/workflows/build.yml

@@ -0,0 +1,51 @@
+name: Build
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+        with:
+          buildkitd-flags: ${{ runner.debug && '--debug' || '' }}
+
+      - name: Login to Github Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN  }}
+
+      - name: Get Commit SHA
+        id: commit_sha
+        run: echo "sha_short=$(git rev-parse --short HEAD)" >> $GITHUB_OUTPUT
+
+      # Build and push the container to the GitHub Container
+      # Repository. The container will be tagged as "latest"
+      # and with the short SHA of the commit.
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: ./Dockerfile
+          pull: true
+          push: true
+          platforms: linux/amd64,linux/arm64
+          cache-from: type=registry,ref=ghcr.io/jb3/ff_bot:latest
+          cache-to: type=inline
+          tags: |
+            ghcr.io/jb3/ff_bot:latest
+            ghcr.io/jb3/ff_bot:${{ steps.commit_sha.outputs.sha_short }}