Streamlined for standard ROS image and easier transfer to new owners etc

[marc-hanheide]

All done in an effort to remove L-CAS specific things and make ths generally useful across the board for the general user. Also uses a minimal image now

It refactors the devcontainer and CI setup to simplify the development environment, standardize on the official ros:humble base image, and modernize the CI workflows. The changes remove custom and organization-specific configurations, streamline dependency installation, and improve compatibility with GitHub Actions and container registries.

Devcontainer and Dockerfile simplification:

• Switches the devcontainer and Dockerfile to use the official ros:humble image as the base, removing CUDA/OpenGL and L-CAS-specific dependencies and user configuration. The container now runs as root by default. (.devcontainer/Dockerfile, .devcontainer/devcontainer.json) [1] [2]
• Simplifies the post-create script (post-create.sh) to only source ROS, update/install dependencies with rosdep, and build the workspace, removing custom shell and git configuration logic. (.devcontainer/post-create.sh)

CI/CD and workflow modernization:

• Updates GitHub Actions workflows to use the latest actions and switches Docker registry from L-CAS to GitHub Container Registry (ghcr.io). Also updates Docker labels to use Open Containers Initiative (OCI) standards. (.github/workflows/build-docker.yml) [1] [2] [3] [4]
• Refactors ROS CI workflow: uses the latest checkout and setup-ros actions, removes ROS 1 and Iron support, and standardizes on ROS 2 Humble. (.github/workflows/ros-ci.yml) [1] [2] [3]
• Updates the devcontainer CI workflow to use the latest actions and simplifies triggers and steps. (.github/workflows/dev-container.yml)
• Adds a new Copilot setup workflow for building and testing the workspace in GitHub Actions using ROS 2 Humble. (.github/workflows/copilot-setup-steps.yml)

Documentation update:

• Simplifies the README.md to reflect the new, streamlined devcontainer setup and usage, removing references to desktop features and L-CAS-specific instructions. (README.md)

Resource requirements:

• Reduces the default devcontainer resource requirements (CPU and memory) for a more lightweight development environment. (.devcontainer/devcontainer.json)