Add ArtifactHub repository metadata and improve Helm chart configuration

- Introduced artifacthub-repo.yml for ownership verification on ArtifactHub.
- Updated release-chart.yaml to publish the ArtifactHub metadata as an OCI artifact.
- Bumped chart version to 0.2.2 and added relevant changes to Chart.yaml.
- Enhanced job-reconcile.yaml by adding a writable /tmp directory for the reconcile job.

.gitea/workflows/release-chart.yaml

@@ -25,6 +25,10 @@ name: Release chart
 # generic OCI artifacts, and a chart sharing the exact repository path with
 # the container image of the same name makes the package listing/type
 # ambiguous. A distinct `charts/` path keeps the two package kinds apart.
+#
+# Also pushes charts/aptly/artifacthub-repo.yml as a companion OCI artifact
+# (tag `artifacthub.io`) on every run, proving ownership of this repository
+# to ArtifactHub — see the "Publish ArtifactHub repository metadata" step.
 on:
   release:
     types: [published]
@@ -104,6 +108,22 @@ jobs:
             --username "${{ secrets.REGISTRY_USER }}" --password-stdin
           helm push "aptly-${{ steps.version.outputs.version }}.tgz" oci://git.morlana.online/f.weber/charts
 
+      # Publishes charts/aptly/artifacthub-repo.yml as its own OCI artifact
+      # (tag `artifacthub.io`) next to the chart — this is how ArtifactHub
+      # verifies ownership of an OCI-based Helm repository; there's no
+      # index.yaml it could otherwise crawl a metadata file out of. Uses the
+      # same registry credentials as the chart push above, nothing
+      # ArtifactHub-specific is needed (ArtifactHub has no publish API to
+      # authenticate against — it only reads the registry).
+      - uses: oras-project/setup-oras@v1
+      - name: Publish ArtifactHub repository metadata (ownership verification)
+        run: |
+          echo "${{ secrets.REGISTRY_TOKEN }}" | oras login git.morlana.online \
+            --username "${{ secrets.REGISTRY_USER }}" --password-stdin
+          oras push git.morlana.online/f.weber/charts/aptly:artifacthub.io \
+            --config /dev/null:application/vnd.cncf.artifacthub.config.v1+yaml \
+            charts/aptly/artifacthub-repo.yml:application/vnd.cncf.artifacthub.repository-metadata.layer.v1.yaml
+
       - name: Attach chart artifacts to the Gitea release
         uses: softprops/action-gh-release@v2
         with: