[Bug] `code --wait` flag not blocking in shell command execution

Bug Description

Bug: code --wait doesn't wait when invoked via Claude Code

### Environment

• macOS (Darwin 25.3.0)
• Shell: zsh
• $EDITOR: "code --wait"

### Steps to reproduce

1. Set export EDITOR="code --wait"
2. In Claude Code, run: `!TMPFILE=$(mktemp) && echo "hello" > "$TMPFILE" && code --wait

"$TMPFILE" && cat "$TMPFILE"`

1. VSCode opens the file, but cat executes immediately without waiting for the tab to

close

### Expected
code --wait should block until the file tab is closed (same as running directly in
terminal)

### Actual
The command does not wait — subsequent commands execute immediately.
This also affects Ctrl+G (chat:externalEditor), which returns empty content.

### Workaround
Using nano as $EDITOR works correctly.

Environment Info

• Platform: darwin
• Terminal: ghostty
• Version: 2.1.76
• Feedback ID: aec7220f-76e8-4a8b-80b0-a8c36042674a

Errors

[{"error":"Error: NON-FATAL: Lock acquisition failed for /Users/umehara/.local/share/claude/versions/2.1.76 (expected in multi-process scenarios)\n    at FvT (/$bunfs/root/src/entrypoints/cli.js:2417:2026)\n    at Lxq (/$bunfs/root/src/entrypoints/cli.js:2417:1170)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-03-16T16:32:30.223Z"}]