[FEAT] Use MapStruct for Mapping Entities and DTOs

[this-Aditya]

Currently, we are using manual converters to transform Java beans into DTOs and vice versa. To enhance efficiency and maintainability, we can utilize MapStruct:
MapStruct is a code generation tool that simplifies the implementation of mappings between Java bean types, following a convention-over-configuration approach.

Read more about it: https://mapstruct.org/