with structuredAttrs lists will be bash arrays which cannot be exported
which will be a issue with some patches and some wrappers like cc-wrapper
this makes it clearer that NIX_CFLAGS_COMPILE must be a string as lists
in env cause a eval failure
The expression now supports having `words.txt` in some place without tens
and tens of megabytes of all the wordlist and spelling dictionaries. Set
`singleWordlist` parameter to the string of region and size settings. For
example:
```
scowl.override{singleWordlist = "en-gb-ise 60";}
```
Should be useful for #34486
