Imports by ImportBot sometimes invisible to ISBN and title searches

When I was searching for [Dnipro - Dnepr. Die Ukraine im Fluss](https://openlibrary.org/works/OL34341053W/Dnipro_-_Dnepr._Die_Ukraine_im_Fluss) by ISBN or title, I could not find it.

When I accidently pasted the author ([Galyna Spodarets](https://openlibrary.org/authors/OL12430446A/Galyna_Spodarets)) into to search field when I wanted to manually import it, it suddenly appeared in the search results.

According to the page history, the book was imported back in February 2023, and I searched for it in late October 2023 - so that was not a coincidence of the book being imported just moments after I searched for it. After I edited the entry, I could find it by searching for ISBN and title, too.

### Evidence / Screenshot (if possible)
I first need to find a new book which I cannot find.

### Relevant url?

### Steps to Reproduce

1. Search for a book by title, get no result
2. Search for a book by ISBN, still get no result
3. Search for the author, suddenly find the book

The only common trait of all the books I encountered was: They were imported by ImportBot. Otherwise, it seems completely random.

* Actual: I would expect ISBN search and title search to find any title who has these two properties
* Expected: Certain books imported by ImportBot cannot be found via ISBN search or title search

### Details

- **Logged in (Y/N)?** Y
- **Browser type/version?** Firefox 119 /64 bit
- **Operating system?** OpenSuse Tumbleweed
- **Environment (prod/dev/local)?** prod

### Proposal & Constraints

I do not know what causes this behaviour and how it can be solved. @seabelis said she noticed it several times as well and assumes it would be somewhat connected to the indexing priorities for imports by ImportBots.

In any way, this bug may cause duplicate entries if either imports are triggered multiple times or librarians add books manually which had already been imported but do not appear in the search results.

### Related files

### Stakeholders

Start by reproducing the ISBN, title, and author searches described for an ImportBot-created book, then compare its search visibility before and after editing. Trace the import and indexing path to identify why these records are omitted; done means affected imported books are discoverable by both ISBN and title without manual editing.

Written by the indexing model from the issue text.