Send book code in the book name API

[RevantCI]

1. Send book code in the book name API
   /booknames?language_code=hin
   Currently only book id is coming and the mapping from book code to book id is done using hard coded data it should be sent from the backend.
   eg. book_code: "exo"

2. Remove language_id as its already in the outside json and is duplicated
   see json below.

{
"language": {
"id": 58,
"code": "hin",
"name": "Hindi"
},
"bookNames": [
{
"id": 546,
"abbr": "निर्ग.",
"short": "निर्गमन",
"long": "निर्गमन",
"book_id": 2,
"language_id": 58
},

[JesniJ]

Test Result

Verified the GET /booknames API in Swagger.

The API now returns the book_code field ( "book_code": "exo") for each book, eliminating the need for frontend hardcoded mapping between book_id and book_code.

Also verified that the redundant language_id field has been removed from each book entry, as the language information is already provided in the parent language object.

No issues were observed during testing.

Moving the issue to done.