Publish landing image to GHCR

Author: rgs2151

.github/workflows/container.yml

@@ -0,0 +1,55 @@
+name: Publish Container
+
+on:
+  push:
+    branches:
+      - expansion
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  packages: write
+
+env:
+  REGISTRY: ghcr.io
+  IMAGE_NAME: ${{ github.repository }}
+
+jobs:
+  publish:
+    name: Build and publish
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v5
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v4
+
+      - name: Log in to GHCR
+        uses: docker/login-action@v4
+        with:
+          registry: ${{ env.REGISTRY }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Generate image metadata
+        id: meta
+        uses: docker/metadata-action@v6
+        with:
+          images: ${{ env.REGISTRY }}/${{ env.IMAGE_NAME }}
+          tags: |
+            type=ref,event=branch
+            type=sha,prefix=sha-
+            type=raw,value=latest,enable=${{ github.ref_name == 'expansion' }}
+
+      - name: Build and push image
+        uses: docker/build-push-action@v7
+        with:
+          context: .
+          file: ./Dockerfile
+          push: true
+          tags: ${{ steps.meta.outputs.tags }}
+          labels: ${{ steps.meta.outputs.labels }}
+          cache-from: type=gha
+          cache-to: type=gha,mode=max

README.md

@@ -50,7 +50,26 @@ docker compose logs -f
 docker compose down
 ```
 
-For a server, either build this repo directly with Compose or publish the image to a registry such as GitHub Container Registry. Docker Hub is optional; GHCR is usually cleaner here because the code already lives on GitHub. A separate server/infrastructure repo can later pull the published image and route `singha.io` to container port `80`.
+On every push to `expansion`, GitHub Actions publishes:
+
+```text
+ghcr.io/rgs2151/landing:expansion
+ghcr.io/rgs2151/landing:latest
+ghcr.io/rgs2151/landing:sha-<commit>
+```
+
+A server/infrastructure repository should pull the image instead of copying this source code:
+
+```yaml
+services:
+  landing:
+    image: ghcr.io/rgs2151/landing:expansion
+    restart: unless-stopped
+    expose:
+      - "80"
+```
+
+Route `singha.io` to container port `80`. Docker Hub is optional; GHCR is the default because the code and Actions pipeline already live on GitHub.
 
 ## Domain