Add docker env

.gitea/workflows/deploy.yml

@@ -24,11 +24,15 @@ jobs:
     steps:
       - name: Verify image exists in registry
         # Fail fast if the user typed a version that was never built. Catches
-        # typos before we touch the gitops repo.
+        # typos before we touch the gitops repo. Uses env-var pattern for
+        # credentials to avoid shell interpolation mangling special characters.
+        env:
+          REG_USER: ${{ secrets.REGISTRY_USERNAME }}
+          REG_PASS: ${{ secrets.REGISTRY_PASSWORD }}
         run: |
           set -euo pipefail
           status=$(curl -sf -o /dev/null -w '%{http_code}' \
-            -u "${{ secrets.REGISTRY_USERNAME }}:${{ secrets.REGISTRY_PASSWORD }}" \
+            -u "$REG_USER:$REG_PASS" \
             "https://${REGISTRY}/v2/${IMAGE}/manifests/${{ inputs.version }}" \
             || true)
           if [ "$status" != "200" ]; then