"""
Schema Package (API Data Validation), DTO(Data Transfer Object)

This package defines Pydantic models (schemas) used for validating incoming
API request data and serializing outgoing API response data. These schemas
ensure data integrity and provide clear contracts for the API.

Modules:
- chat_schema.py: Defines schemas for chat completion requests, responses,
                  messages, and plot data structures used in the API.
"""