Apply server actions transform to `node_modules` in route handlers (#89316)
The server actions transform, which handles the `'use cache'` directive,
was not being applied to `node_modules` when imported from route
handlers. This caused `'use cache'` functions from dependencies to fail
with errors like `"cacheLife() can only be called inside a 'use cache'
function"``.
The issue was that the `AppRoute` context used `internal_custom_rules`
for its foreign code module options, which did not include the server
actions transform. This is inconsistent with `AppRSC` (App Router
pages), which correctly uses `foreign_next_server_rules` that includes
the transform.
The fix extends `foreign_next_server_rules` with `internal_custom_rules`
and uses it for the foreign code context in `AppRoute`, matching the
pattern used by `AppRSC`.