[feature]:Library Demo Enhancement to add CRUD Operations

[hindochahitarth]

Issue Description: GraphQL CRUD for Library Demo
🔖 Enhancement description Currently, the Library Demo application is a read-only GraphQL service. I propose introducing CRUD (Create, Read, Update, Delete) capabilities through GraphQL Mutations.

Proposed improvements:

GraphQL Mutations: Add addBook, updateBook, deleteBook, addAuthor, and deleteAuthor operations.
DTO Implementation: Introduce BookInput and AuthorInput for secure and clean data handling.
🎤 Why should this be worked on? A read-only API limits the utility of a library management system. Adding CRUD operations allows for dynamic data management and provides a complete example of GraphQL usage.

Team: Team 137 GDG CHARUSAT 💻 Repository:
hindochahitarth/samples-java

[github-actions]

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