When Claude sessions were terminated using KillSession(), bash subprocesses
spawned by Claude's Bash tool could survive because they ignore SIGHUP.
This caused zombie processes to accumulate over time.
Changed all critical session termination paths to use KillSessionWithProcesses()
which explicitly kills all descendant processes before terminating the session.
Fixes: gt-ew3tk
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
When gt doctor runs, it now detects and kills zombie sessions - tmux
sessions that are valid Gas Town sessions (gt-*, hq-*) but have no
Claude/node process running inside. These occur when Claude exits or
crashes but the tmux session remains.
Previously, OrphanSessionCheck only validated session names but did not
check if Claude was actually running. This left empty sessions
accumulating over time.
Fixes#472
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
