The canonical BibTeΧ template for @inbook (i.e. https://www.bibtex.com/t/template-inbook/) includes "chapter" as a metadata field.

See full template here:
```
@inbook{citekey,
author = "",
title = "",
chapter = "",
publisher = "",
year = "",
volume = "",
number = "",
series = "",
type = "",
address = "",
edition = "",
month = "",
pages = "",
note = "",
annote = ""
}
```

Even the most minimal template specified by BibTeΧ includes the chapter field:

```
@inbook{citekey,
editor = "",
title = "",
chapter = "",
publisher = "",
year = ""
}
```

When thinking of a "book section", in practice, this most commonly means "book chapter".

Yet Zotero's "book section" metadata does not include "chapter" as a field. This is problematic—it means I've been unable to make use of the chapter metadata included in every single book chapter BibTeΧ file I've imported into my library. Instead, I've had to go and backfill chapter information in the "extra" field in these items, which is extra manual work and also makes it more difficult to filter on and query (both in the Zotero UI and with the API).

Please fix this ASAP! It's been missing for years, and I can't think of a good reason why.