Remove dev container config from repo (for now)

[RembrandtK]

Removing dev container config from the repo for now.

Although in the long term it would be good to have a dev container configuration, currently:

1. AFAIK I am the only one using it.
2. The current config has dependencies on local setup and mixes repo concerns and personal preferences. This might be resolved as the config evolves, but anyone else would currently not have a great experience (due to dependencies and the rate of change).
3. The config is evolving though ongoing tweaks while I work on other items causes friction due to needing to patch multiple branches.

I am still using dev containers but my local setup now associates dev container configs with repos without touching the repo itself. This works well for me, while avoiding dependencies on repo configuration.

A dev container configuration might well be re-introduced in future when more stable. In the meantime if you would like to use dev containers let me know, and can share my config and approach, and potentially (if ready) add a config back if ready.

[Copilot]

Pull Request Overview

This PR removes the dev container configuration from the repository based on the maintainer's assessment that it's not ready for general use and creates maintenance friction. The config has dependencies on local setup, mixes personal preferences with repo concerns, and is actively evolving in ways that require patching across multiple branches.

• Removes all dev container configuration files from the .devcontainer/ directory
• Eliminates Docker and Docker Compose setup files
• Removes shell scripts for project and host setup
• Clears documentation and sample environment files

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
.devcontainer/setup-git-signing.sh	Removes SSH signing setup script
.devcontainer/sample-graph.env	Removes sample environment configuration
.devcontainer/project-setup.sh	Removes project-specific setup script
.devcontainer/host-setup.sh	Removes host environment setup script
.devcontainer/docker-compose.yml	Removes Docker Compose service definition
.devcontainer/devcontainer.json	Removes VS Code dev container configuration
.devcontainer/README.md	Removes dev container documentation
.devcontainer/Dockerfile	Removes container image definition

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.84%. Comparing base (cd59452) to head (b7ca26d).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1231   +/-   ##
=======================================
  Coverage   82.84%   82.84%           
=======================================
  Files          47       47           
  Lines        2093     2093           
  Branches      620      620           
=======================================
  Hits         1734     1734           
  Misses        359      359           

Flag	Coverage Δ
unittests	82.84% <ø> (ø)

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