There are no externally visible orphans `Cardano.Ledger.[Era].Rules` modules.

Such imports shouldn't be necessary, aside from top level `Cardano.Ledger.[Era]` module:
```haskell
import Cardano.Ledger.[Era].Rules ()
```
There are no externally visible orphans `Cardano.Ledger.[Era].Rules` modules.

We need to make sure these are removed and if removal causes issues we need to get to the bottom of what is the source of such issue

_Originally posted by @lehins in https://github.com/IntersectMBO/cardano-ledger/pull/5816#discussion_r3226335026_

Search the repository for imports of Cardano.Ledger.[Era].Rules and inspect the top-level Cardano.Ledger.[Era] modules that are intended to remain. Remove the unnecessary Rules imports, then run the relevant project checks to identify any failures and determine whether they reveal a missing dependency. Done means those externally visible orphan-module imports are gone without breaking the checks.

Written by the indexing model from the issue text.