refactor requests related dto with pydantic

dto/requests.py

@@ -1,16 +1,14 @@
-from dataclasses import dataclass
+from pydantic import BaseModel
 from typing import Literal
 from uuid import UUID
 
 
-@dataclass
-class GameStartRequest:
+class GameStartRequestDTO(BaseModel):
     """Request model for starting a new game."""
     player_name: str
 
 
-@dataclass
-class GameDecisionRequest:
+class GameDecisionRequestDTO(BaseModel):
     """Request model for making a game decision."""
     decision: Literal["Accept", "Reject"]
     session_id: UUID