Auto-deploy ROS nav Docker via DimOS docker module

[spomichter]

Issue

The ROS nav Docker image should be automatically downloaded/deployed by a DimOS docker module when needed.

Currently, users need to manually pull or build the ROS nav container. DimOS should handle this automatically when running navigation blueprints.

Tasks

• Create a DimOS docker module for ROS nav
• Auto-download from registry on first use
• Handle version pinning and updates
• Integration with navigation blueprints (auto-start when nav is used)

Context

Part of the G1 navigation cleanup — see #1267

Depends on: Auto-build ROS nav Docker (#1268)