Fix devcontainer CLI PATH resolution for nvm environments

[marchingphoenix]

Summary

This PR fixes an issue where the devcontainer CLI fails to execute in environments where Node.js is managed by nvm. The problem occurs when VS Code is launched from the OS application launcher rather than a terminal, causing the nvm bin directory to not be on the PATH inherited by child processes.

Changes

• PATH augmentation in executeCommand: When the devcontainer CLI path is an absolute path, its parent directory is now prepended to the PATH environment variable passed to child processes. This ensures that the devcontainer CLI (a #!/usr/bin/env node script) can find the correct Node.js binary in the same directory.
• Test coverage: Added comprehensive tests to verify:
  • PATH is correctly augmented when devcontainerCliPath is an absolute path
  • PATH remains unchanged when devcontainerCliPath is a bare command name

Implementation Details

• The fix extracts the binary directory from absolute paths using path.dirname() and prepends it to the existing PATH using path.delimiter
• Only absolute paths trigger PATH modification; relative or bare commands are left unchanged
• The environment object is passed to the exec() call to ensure the modified PATH is used by child processes

https://claude.ai/code/session_012wQn8VuzGxVXtDYbwmekUk