Desktop app leaves orphaned child processes consuming 100% CPU

Description

The Claude desktop app (v1.1.8629) does not properly terminate child claude processes when a session is closed. This results in orphaned processes running indefinitely at 100% CPU.

Reproduction

1. Use Claude desktop app to start a Claude Code session (local agent mode)
2. Close/leave the session
3. The child claude process (Claude Code binary) continues running in the background at 100% CPU

Observed behavior

• Orphaned process: claude (v2.1.78) with --resume flag, launched via desktop app
• CPU usage: 100% constant
• The process accumulated 1746 minutes (~29 hours) of CPU time over 3 days before being manually killed
• kill <pid> (SIGTERM) was ignored — required kill -9 (SIGKILL) to terminate
• Mac CPU temperature reached 90°C, dropped to 52°C after killing the process

Expected behavior

Child processes should be terminated when the parent session is closed. At minimum, the process should respond to SIGTERM gracefully.

Environment

• macOS Darwin 25.3.0 (Apple Silicon)
• Claude desktop app v1.1.8629
• Claude Code v2.1.78