Extend `evil` test suite to account for VFS writes

Extend the `evil` test suite to include tests that will perform 'evil' writes to the host via the guest. ~~We currently only account for reads, so we should account for writes too.~~

Locate the `evil` test suite and first read the existing cases covering guest reads of the host VFS. Add comparable write scenarios that exercise host writes through the guest, then run the relevant test suite and confirm those writes are detected or handled as expected.

Written by the indexing model from the issue text.