## Problem
Claude processes were accumulating as orphans, with 100+ processes piling up
daily. Every `gt handoff` (used dozens of times/hour by crew) left orphaned
processes because `tmux respawn-pane -k` only sends SIGHUP, which Node/Claude
ignores.
## Root Cause
Previous fixes (1043f00d, f89ac47f, 2feefd17, 1b036aad) were laser-focused on
specific symptoms (shutdown, setsid, done.go, molecule_step.go) but never did
a comprehensive audit of ALL RespawnPane call sites. handoff.go was never
fixed despite being the main source of orphans.
## Solution
Added KillPaneProcesses() call before every RespawnPane() in:
- handoff.go (self handoff and remote handoff)
- mayor.go (mayor restart)
- crew_at.go (new session and restart)
KillPaneProcesses explicitly kills all descendant processes with SIGTERM/SIGKILL
before respawning, preventing orphans regardless of SIGHUP handling.
molecule_step.go already had this fix from commit 1b036aad.
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
94c2d71c13