The runner is an application, not a library. `act/model` and
`act/exprparser` were the last packages anything outside this repository
consumed and they now live in actionslib, so nothing needs the rest of
`act` to be importable, and keeping it importable invites the coupling
that was just removed.
Import paths only, the files are unchanged.
Assisted-by: Codet:GPT-5.1-Codex
