ci: add pre-verification step to catch failures early

.gitea/workflows/build-push.yml

@@ -51,6 +51,44 @@ jobs:
           SHORT_SHA=$(git rev-parse --short HEAD)
           echo "short_sha=${SHORT_SHA}" >> $GITHUB_OUTPUT
 
+      - name: Pre-verify Docker and Registry
+        run: |
+          echo "=== Docker Setup Verification ==="
+          echo "✓ DOCKER_HOST: ${DOCKER_HOST}"
+          echo "✓ DOCKER_TLS_VERIFY: ${DOCKER_TLS_VERIFY}"
+          echo "✓ DOCKER_CERT_PATH: ${DOCKER_CERT_PATH}"
+          echo ""
+          echo "=== Docker Daemon Check ==="
+          if ! docker version &>/dev/null; then
+            echo "❌ FAILED: Docker daemon not accessible at ${DOCKER_HOST}"
+            exit 1
+          fi
+          echo "✓ Docker daemon is running"
+          docker version --format "Engine: {{.Server.Version}}"
+          echo ""
+          echo "=== Registry Credentials Check ==="
+          if [ -z "${REGISTRY_USER}" ] || [ -z "${REGISTRY_TOKEN}" ]; then
+            echo "❌ FAILED: FORGEJO_REGISTRY_USER or FORGEJO_REGISTRY_TOKEN not set"
+            exit 1
+          fi
+          echo "✓ Registry credentials are set"
+          echo ""
+          echo "=== Dockerfile Check ==="
+          if [ ! -f Dockerfile ]; then
+            echo "❌ FAILED: Dockerfile not found"
+            exit 1
+          fi
+          echo "✓ Dockerfile exists"
+          echo ""
+          echo "=== Image Tag Check ==="
+          echo "✓ IMAGE tag will be: ${IMAGE}:${{ steps.sha.outputs.short_sha }}"
+          echo "✓ Latest tag will be: ${IMAGE}:latest"
+          echo ""
+          echo "=== All pre-checks passed ==="
+        env:
+          REGISTRY_USER: ${{ secrets.FORGEJO_REGISTRY_USER }}
+          REGISTRY_TOKEN: ${{ secrets.FORGEJO_REGISTRY_TOKEN }}
+
       - name: Registry login
         run: |
           echo "${REGISTRY_TOKEN}" | docker login "${REGISTRY}" \