[Vamsi-2581]

Summary

Fixes #98. run_command now captures stdout and stderr in temporary files and waits for the shell process itself, so backgrounded command lists do not keep pipe readers blocked waiting for EOF.

Root cause

The shell can exit while a background child still holds inherited stdout/stderr pipes open. The existing concurrent readers waited for those pipes to close before returning, causing run_command to block until the background job exited or the timeout fired.

Changes

• Capture process output in temporary files so inherited descriptors do not keep the caller waiting.
• Preserve the existing process session and timeout cleanup behavior.
• Add a regression test for the reported echo && sleep ... & pattern, synchronized to ensure the foreground output has been written before the shell returns.

Validation

• Added regression coverage; tests were not run locally.
• The required lint and type-check workflows are awaiting maintainer approval for this fork PR.
• This contribution was prepared with assistance from OpenAI Codex.