The bootstrap key generated during implementation was lost, and its
replacement was pasted into the wrong repository's secret store — Gitea
secrets neither cross repos nor read back, so neither is usable. The private
half of this one lives in punktfunk-plugin-index's own INDEX_SIGNING_KEY,
which is the only thing that signs the catalog.
Nothing has shipped pinning any of these, so this is a straight replacement
of slot 0; the second slot stays reserved for a genuine rotation.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>