Book cards should show the number of pages

### Proposal

Dear developers,
Would you please consider adding the number of pages to book cards?

Here's how it would look:

Thank you for considering my suggestion.

### Justification

### Breakdown

#### Requirements Checklist

* [ ]

#### Related files

*

#### Stakeholders

*

#### Instructions for Contributors

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No files, tests, or entry points are named. Start by locating the book-card implementation and checking how page-count data is exposed; done means book cards visibly show the number of pages, matching the proposal image.

Written by the indexing model from the issue text.