CLI should not raise error on local action paths, when asked to ignore local actions

The gh-actions-lock should probably not error out when I explicitly ask it not to migrate local actions

Plus the message "which are not supported" is incorrect.

```
gh actions-lock --rescan --no-migrate-local-actions
! LOCAL-ACTION .github\workflows\release-test-github-actions.yml
workflow uses local path actions which are not supported; remove local path actions to continue using the lockfile
✗ 1 of 13 workflows failed: 1 local-action

Resolution record: C:\Users\JesseHouwing\AppData\Local\gh-actions-lock\logs\run-20260818-193150.723.json
```

OR execution should fail... But right now a mix of `./` and pinned actions just works.

Start by reproducing the reported gh actions-lock --rescan --no-migrate-local-actions command with a workflow mixing ./ local actions and pinned actions. Trace how the CLI handles local actions under that flag, then clarify whether it should ignore them or fail consistently, update the misleading message, and add regression coverage for the chosen behavior.

Written by the indexing model from the issue text.