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.

Apikeys.ipynb

@@ -15,9 +15,9 @@
     }
    ],
    "source": [
-    "from backend.ApiKeys.openai_apikey import OpenAICredencial\n",
-    "from backend.ApiKeys.openai_apikey_mmr import OpenAICredencialRepo  # Ajusta si está en otro módulo\n",
-    "from backend.ConexionSql.Postgres_conexion import PostgresConexion\n",
+    "from src.ApiKeys.openai_apikey import OpenAICredencial\n",
+    "from src.ApiKeys.openai_apikey_mmr import OpenAICredencialRepo  # Ajusta si está en otro módulo\n",
+    "from src.ConexionSql.Postgres_conexion import PostgresConexion\n",
     "\n",
     "# 1. Crear instancia de conexión (asegúrate de configurar bien tu conexión en Base_conexion)\n",
     "from entrypoint.init_db import db_credencial\n",
@@ -36,7 +36,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "from backend.ConexionApis.OpenAi_conexion import OpenAICliente\n",
+    "from src.ConexionApis.OpenAi_conexion import OpenAICliente\n",
     "\n",
     "cliente = OpenAICliente(credencial_openai)\n",
     "\n",