fix(helm): push Artifact Hub metadata from helm/ so the layer title matches

Dry-ran the publish sequence against a local OCI registry, which surfaced one
divergence from Artifact Hub's documented command: passing a path-qualified
argument to oras records the layer's title annotation as
`helm/artifacthub-repo.yml` rather than the bare `artifacthub-repo.yml` the
docs produce. Artifact Hub selects the layer by media type, so this was
probably harmless, but there is no reason to diverge from the documented
form. Running the step from helm/ reproduces it exactly.

Everything else in the sequence behaved as intended against a real registry:
helm push derives charts/sim:1.9.1 from the chart name and version, the
digest grep extracts it, the metadata lands with both documented media types
under the artifacthub.io tag, the chart and metadata tags coexist without
disturbing each other, and helm pull round-trips to an identical sha256.

Also confirmed the overwrite hazard behind the fail-closed guard is real
rather than theoretical: re-pushing modified content under an existing
version moved the tag, so a pinned consumer would have silently received
different bytes.

Author: waleedlatif1

.github/workflows/helm.yml

@@ -344,11 +344,15 @@ jobs:
       - name: Publish Artifact Hub metadata
         env:
           REPOSITORY: ${{ steps.package.outputs.repository }}
+        # Run from `helm/` so the layer's title annotation is the bare
+        # `artifacthub-repo.yml`, matching Artifact Hub's documented command. A
+        # path-qualified argument records `helm/artifacthub-repo.yml` instead.
+        working-directory: helm
         run: |
           set -euo pipefail
           oras push "${REPOSITORY}:artifacthub.io" \
             --config /dev/null:application/vnd.cncf.artifacthub.config.v1+yaml \
-            helm/artifacthub-repo.yml:application/vnd.cncf.artifacthub.repository-metadata.layer.v1.yaml
+            artifacthub-repo.yml:application/vnd.cncf.artifacthub.repository-metadata.layer.v1.yaml
 
       - name: Summary
         env: