Removing a package from the repo forces Hermit to sync frequently

If a package is not found after syncing the sources, we should return an error telling the user to fix their environment

Start by tracing the package-sync path that handles a package missing after source synchronization. Confirm how repeated syncing is triggered and how errors are reported. Done means the user receives an error directing them to fix their environment when the package cannot be found after syncing.

Written by the indexing model from the issue text.