Update requirements.txt for Pydantic v2 compatibility

- Updated pydantic version constraint to >=2.0.0,<3.0.0
- Added pydantic-settings>=2.0.0,<3.0.0 dependency
- Ensures compatibility with BaseSettings import from pydantic-settings

requirements.txt

@@ -6,7 +6,8 @@ uvicorn[standard]>=0.20.0,<0.25.0
 httpx>=0.24.0,<0.26.0
 
 # Data validation
-pydantic>=1.10.0,<2.0.0
+pydantic>=2.0.0,<3.0.0
+pydantic-settings>=2.0.0,<3.0.0
 
 # Environment management
 python-dotenv>=0.19.0,<1.0.0