add action to build docker containers

.github/workflows/build-docker.yml

@@ -0,0 +1,62 @@
+---
+
+on: 
+  push:
+    branches:
+      - main
+      - develop
+      - feature-42
+
+jobs:
+  build-docker:
+    runs-on: ubuntu-latest
+    env:
+      registry: gitea.cuqmbr.xyz
+    steps:
+      - name: Login to Docker Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{env.registry}}
+          username: ${{vars.DOCKER_USER}}
+          password: ${{secrets.DOCKER_TOKEN}}
+      # Using instead of checkout action.
+      # https://gitea.com/gitea/act_runner/issues/164#issuecomment-921571
+      - name: Add SSH key
+        env:
+            SSH_AUTH_SOCK: /tmp/ssh_agent.sock
+        run: |
+            mkdir -p /home/runner/.ssh
+            ssh-keyscan gitea.cuqmbr.xyz >> /home/runner/.ssh/known_hosts
+            echo "${{secrets.SSH_PULL_KEY}}" > /home/runner/.ssh/github_actions
+            chmod 600 /home/runner/.ssh/github_actions
+            ssh-agent -a $SSH_AUTH_SOCK > /dev/null	
+            ssh-add /home/runner/.ssh/github_actions
+      - name: Checkout repository
+        env:
+          SSH_AUTH_SOCK: /tmp/ssh_agent.sock
+        run: |
+          git init
+          git remote add origin git@gitea.cuqmbr.xyz:bebrashield/server-survival.git
+          git fetch --depth 1 origin ${{ github.ref }}
+          git checkout FETCH_HEAD
+          git lfs pull
+      # - name: Checkout repository
+      #   uses: actions/checkout@v4
+      #   with:
+      #     token: ${{secrets.PULL_TOKEN}}
+      #     lfs: true
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Build and push
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          file: ./Dockerfile
+          platforms: linux/arm64,linux/amd64
+          push: true
+          # TODO: split tag names into multiple lines
+          tags: |
+            ${{env.registry}}/${{github.repository_owner}}/${{github.event.repository.name}}/${{github.ref_name}}:${{github.sha}}
+            ${{env.registry}}/${{github.repository_owner}}/${{github.event.repository.name}}/${{github.ref_name}}:latest