Add OpenAI and PostgreSQL credential management

- Implemented OpenAICredencial class for managing OpenAI API keys.
- Created OpenAICredencialModel and OpenAICredencialMapper for SQLAlchemy integration.
- Developed OpenAICredencialRepo for CRUD operations on OpenAI credentials.
- Established OpenAICliente class for interacting with OpenAI API.
- Introduced PostgresCredencial class for managing PostgreSQL connection details.
- Created PostgresCredencialModel and PostgresCredencialMapper for SQLAlchemy integration.
- Developed PostgresCredencialRepo for CRUD operations on PostgreSQL credentials.
- Added base connection class and PostgreSQL connection implementation.
- Included environment variable loading for sensitive data management.

llms/Modelos/Openai_model.py

@@ -1,5 +1,5 @@
 from llms.Modelos.Base_model import ModeloABC
-from backend.ConexionApis.OpenAi_conexion import OpenAICliente
+from src.ConexionApis.OpenAi_conexion import OpenAICliente
 
 class ModeloOpenAI(ModeloABC):
     def __init__(

llms/Modelos/Openai_model_mmr.py

@@ -2,8 +2,8 @@ import os
 from dotenv import load_dotenv
 from sqlalchemy import Column, Integer, String, Float, Boolean
 
-from backend.ConexionSql.Base_conexion import ConexionBase
-from backend.base import Base
+from src.ConexionSql.Base_conexion import ConexionBase
+from src.base import Base
 from llms.Modelos.Openai_model import ModeloOpenAI  # Clase real de lógica
 
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