A Next.js Server Action (an export of a "use server" file) that no code in
the analyzed project references: no import-and-call, no action={fn} JSX
binding, no <form action={fn}>. This is the cross-graph “declared but zero
consumers” direction, reclassified out of unused-export for "use server"
files so the finding carries the action-specific signal. It does NOT mean the
endpoint is unreachable: Next still registers the action id, so it stays
POST-able. It means no project code calls it (likely forgotten / dead, and a
candidate for removal to shrink surface area).