Search entities should allow filtering by book or chapter id

[helderjsm]

API Endpoint or Feature

The API endpoint for searching entities should allow for filtering by chapter_id and or book_id.

Use-Case

When using bookstack as documentation repository for multiple projects one requires the ability to search by book_id to limit results to the project that it applies to.

Additional context

Currently trying to filter by tags returns entities from different books which requires in-code pagination.
Not only pagination in code is slower and forces too much data to be returned and parsed from the API but also the fact that the sorting is broken makes it impossible to obtain a list of paginated results after 100 entities.

Please note that there is a separate bug that makes correct pagination impossible when using filters. Searching for entities with paginated results leads to random sorting, causing inconsistencies in the order of results on subsequent result pages.

[helderjsm]

Pull request open here #5402.