Add MongoDB support in Console

[graikhel-intel]

Description

As a user, I want Console to support MongoDB as a database backend so that deployments can use MongoDB in environments where it is preferred or already used.

Currently Console supports PostgreSQL and SQLite. To align with capabilities currently supported by MPS, we should also add support for MongoDB.

This also aligns with the longer-term goal of supporting the Discovery feature, where collected data may be unstructured or vary in schema across devices and platforms.

For database handling, we will continue to follow the existing pattern:

• Non-secret data is stored in the database.
• Secrets are stored in Vault or Secret Service.

Open Questions

• Should MongoDB be implemented directly, or should we introduce a pluggable NoSQL storage layer using Go interfaces so other document databases could be supported in the future?

Acceptance Criteria

• Console supports MongoDB as a database backend.
• PostgreSQL/SQLite support continues to work for both enterprise and cloud deployments.
• Updates to docker-compose.yml/Dockerfile if any.
• Non-secret data is stored in the configured database.
• Secrets continue to be stored in Vault.
• Documentation is updated to describe how to configure MongoDB for Console.
• Standard DoD