Add two new health checks to gt doctor:
1. orphan-sessions: Detects Gas Town tmux sessions (gt-*) that do not
match expected patterns (mayor, deacon, rig-witness, rig-refinery,
rig-polecat). Validates rig names against actual workspace structure.
2. orphan-processes: Detects Claude/claude-code processes without a
tmux parent. Walks process tree to find orphaned instances that
may be consuming resources.
Both checks support --fix to clean up detected orphans:
- Kills orphaned tmux sessions
- Sends SIGINT (then SIGKILL) to orphaned processes
Closes gt-qsvq.
Generated with Claude Code
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>