chore: rename Helm chart from antigravity to devcontainer

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Co-Authored-By: Claude <noreply@anthropic.com>
Co-Authored-By: Happy <yesreply@happy.engineering>

.github/workflows/helm-release.yaml

@@ -34,4 +34,4 @@ jobs:
       - name: Push chart to GHCR
         run: |
           CHART_VERSION=$(helm show chart chart/ | grep '^version:' | awk '{print $2}')
-          helm push cpfarhood-${CHART_VERSION}.tgz oci://ghcr.io/cpfarhood/charts
+          helm push devcontainer-${CHART_VERSION}.tgz oci://ghcr.io/cpfarhood/charts