ci: Add docker and git to workflow dependencies

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Co-Authored-By: Claude <noreply@anthropic.com>

.gitea/workflows/build-container.yml

@@ -0,0 +1,58 @@
+# Gitea Actions workflow for StarPunk
+# Builds and pushes container images on version tags
+
+name: Build Container
+
+on:
+  # Trigger on version tags
+  push:
+    tags:
+      - 'v[0-9]+.[0-9]+.[0-9]+'
+  # Allow manual trigger from Gitea UI
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: docker
+    steps:
+      - name: Install dependencies
+        run: |
+          if command -v apk > /dev/null; then
+            apk add --no-cache nodejs npm docker git
+          elif command -v apt-get > /dev/null; then
+            apt-get update && apt-get install -y nodejs npm docker.io git
+          elif command -v yum > /dev/null; then
+            yum install -y nodejs npm docker git
+          fi
+
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Extract registry URL
+        id: registry
+        run: |
+          # Extract hostname from server URL (remove protocol)
+          REGISTRY_URL=$(echo "${{ github.server_url }}" | sed 's|https://||' | sed 's|http://||')
+          echo "url=${REGISTRY_URL}" >> $GITHUB_OUTPUT
+
+      - name: Login to Gitea Container Registry
+        uses: docker/login-action@v3
+        with:
+          registry: ${{ steps.registry.outputs.url }}
+          username: ${{ github.actor }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v5
+        with:
+          context: .
+          file: ./Containerfile
+          push: true
+          tags: |
+            ${{ steps.registry.outputs.url }}/${{ github.repository }}:${{ github.ref_name }}
+            ${{ steps.registry.outputs.url }}/${{ github.repository }}:latest
+          cache-from: type=gha
+          cache-to: type=gha,mode=max