Auto-build ROS nav Docker image

[spomichter]

Issue

The ROS navigation stack Docker image needs to be automatically built as part of the DimOS build/CI process.

Currently, there's manual intervention required to build the ROS nav Docker container.

Tasks

• Add Docker build automation for ROS nav stack
• Integrate into CI/CD pipeline
• Version tagging strategy for nav stack images
• Registry publishing (if applicable)

Context

Part of the G1 navigation cleanup — see #1267

Related: Auto-deployment via DimOS docker module (#TBD)