Fix package-and-publish failure on empty artifact repository

[Copilot]

gh release create returns HTTP 422 ("Repository is empty") because GitHub requires at least one commit before a release can be attached. The mirror step that pushes the initial commit ran after the publish step, so the repo was always empty at publish time.

Changes

• Reorder steps: "Mirror Zip Packages" now runs before "Publish Release", ensuring the artifact repo has at least one commit when gh release create is called
• Handle empty-repo clone: --depth 1 fails fatally on a repo with no history; added a fallback to a full clone so the mirror step can initialize an empty repo

- name: Mirror Zip Packages Into Artifact Repository
  run: |
    if ! gh repo clone "$ARTIFACT_REPO" artifact-repo -- --depth 1 2>/dev/null; then
      gh repo clone "$ARTIFACT_REPO" artifact-repo
    fi
    ...

- name: Publish Release To Artifact Repository
  run: |
    gh release create ...