Suggest an idea for Knip

Description

knip.json can retain workspace-specific config keys after a workspace is removed or renamed. Knip already hints at stale ignoreWorkspaces entries, but stale workspaces keys go unreported.

{
  "workspaces": {
    "packages/a": {},
    "services/stale": {}
  }
}

If services/stale no longer matches any discovered workspace, it stays silent during a normal run.

Use case

In a large monorepo, services are added, renamed, and removed regularly, so workspaces overrides (ignoreDependencies, entry, project, plugins) easily go stale. They're hard to spot manually and make config cleanup harder after service lifecycle changes.

Proposed behavior

Emit a configuration hint for workspaces keys that match no discovered workspace:

Configuration hints
services/stale  knip.json  Remove from workspaces

For glob keys, report only when the key matches no workspace at all.