0.2.1 shipped a mix.exs that read the workspace dependency-source registry from
two directories above itself. That path exists in this checkout and not inside a
published tarball, so any consumer resolving execution_plane from Hex failed
while Mix loaded the dependency's project.

Resolution now treats an absent registry as the ordinary state of a published
package and falls back to the hex: requirement stated at the call site. Local
development still resolves siblings by path.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>