NotesAPI task submitted by Prem kumar R

[prem-ramamoorthy]

feat: Implement Notes Management API with FastAPI

Description

This PR implements a complete Notes Management REST API using FastAPI with all required and bonus features.

Method	Endpoint	Status Code	Description
GET	/notes	200	Get all notes
POST	/notes	201	Create new note
GET	/notes/{id}	200/404	Get specific note
PUT	/notes/{id}	200/404	Update note
DELETE	/notes/{id}	204/404	Delete note