Refactor database configuration and user management

- Updated .env.example to consolidate SQL Server credentials under PANEL_MSSQL_* variables.
- Removed deprecated docker-compose.postgres.yml file.
- Adjusted docker-compose.yml to utilize new SQL Server credential structure.
- Enhanced README.md with Docker build and push instructions.
- Refined database schema in schema.sql to align with new user and permission structures.
- Updated init-database.js to reflect changes in user and session table names.
- Modified user management functions in users.ts to accommodate new database schema.
- Streamlined API routes to utilize PostgreSQL for user and database management.
- Improved error handling and logging in various server routes.

.env.example

@@ -1,22 +1,11 @@
-# SQL Server - Servidor Primary (.202)
-DB_PRIMARY_HOST=104.197.7.202
-DB_PRIMARY_USER=sa
-DB_PRIMARY_PASS=Clave.2025
-DB_PRIMARY_DB=master
+# Credenciales SQL Server (mismo usuario en todos los nodos salvo sql_password en database_nodes).
+# Si no defines PANEL_MSSQL_*, se usan DB_PRIMARY_* / DB_SECONDARY_* como respaldo.
+PANEL_MSSQL_USER=sa
+PANEL_MSSQL_PASSWORD=Clave.2025
+# En contenedor Docker: reescribe localhost en server_name → host.docker.internal
+# PANEL_MSSQL_DOCKER=true
 
-# SQL Server - Servidor Secondary (.152)
-DB_SECONDARY_HOST=104.192.7.152
-DB_SECONDARY_USER=sa
-DB_SECONDARY_PASS=Clave.2025
-DB_SECONDARY_DB=master
-
-# SQL Server - Azure/CONTROLDESK
-DB_AZURE_HOST=104.192.7.152
-DB_AZURE_USER=sa
-DB_AZURE_PASS=Clave.2025
-DB_AZURE_DB=CONTROLDESK
-
-# PostgreSQL - Base de datos de usuarios (Docker local)
+# PostgreSQL - Usuarios del panel + catálogo ControlDesk (tablas a24c.* las crea otra app)
 DB_POSTGRES_HOST=localhost
 DB_POSTGRES_PORT=5432
 DB_POSTGRES_USER=postgres