Add Hindi (hi) language translation file for Adminer

Add Hindi (hi) language translation file for Adminer

This commit adds a new Hindi (hi) translation file for Adminer, based on the existing Bengali (bn) language file.

All interface strings have been translated from Bengali to Hindi to make Adminer more accessible to Hindi-speaking users. The structure of the file follows the format used in other language files within the repository.

The translations were carefully reviewed to ensure accuracy, readability, and consistency with the context of the Adminer application.

File added:
- lang/hi.inc.php

Looking forward to your feedback and happy to make any improvements as needed!