[split] Main changes — from #21

[pull-apart]

Automated split from #21.

Context

This is the main / behavior half of an automated split from #21.

Changes in this PR:

• utilities/console.py: Imported pty, shlex, subprocess, pexpect.fdpexpect modules
• Imported TimeoutExpiredError from timeout_sampler
• Added _proc attribute to Console class to store subprocess handle
• Added _spawn_console() method to create a pty pair and wrap subprocess in fdspawn
• Added _terminate_proc() method for graceful subprocess shutdown
• Modified connect() method to use _spawn_console() and _terminate_proc()
• Modified disconnect() method to use _terminate_proc() and check subprocess status
• Modified console_eof_sampler() to internally call _spawn_console() and simplify parameters

How this split maps your changes

• Refactor branch (split-pr-21-1783426939-refactor): files classified as cleanup / mechanical work:
  • utilities/unittests/test_console.py
• Main branch (split-pr-21-1783426939-main): files classified as feature / behavior work:
  • utilities/console.py

Merge order

Merge the refactor PR first if it touches shared files or would conflict with the main PR; then merge the main PR. Resolve conflicts in the usual way if both branches touch the same lines.

Refactor PR: #35