Add book app features

[wtf4ev]

Implemented the create_book and list_all_books features as part of the Git & GitHub Enablement assignment.

Changes made:

• Added create_book.txt
• Added list_all_books.txt
• Added ascending order description
• Merged feature branch into develop

[greptile-apps]

Greptile Summary

This PR adds text descriptions for two book app features. The main changes are:

• Added a create-book feature description.
• Added a list-all-books feature description.
• Documented ascending order for the book list.

Confidence Score: 5/5

This looks safe to merge.

• No blocking issues found in the changed code.

Important Files Changed

Filename	Overview
Reva_book_app/add_books_feature/create_book.txt	Adds a one-line text description for the create-book feature.
Reva_book_app/add_books_feature/list_all_books.txt	Adds a two-line text description for listing created books in ascending order.

_{Reviews (1): Last reviewed commit: "Merge branch 'feature' into develop" | Re-trigger Greptile}