Status line disappears after Task (subagent) completes and never returns

Description

Custom status line configured via .claude/settings.json disappears after a Task (subagent) completes and never reappears for the rest of the session.

Setup

.claude/settings.json:

{
  "statusLine": {
    "type": "command",
    "command": "./.claude/statusline.sh"
  }
}

The script reads JSON from stdin and outputs a single line (model, context %, session info).

Steps to reproduce

1. Configure a custom status line via .claude/settings.json pointing to a shell script
2. Start a session -- status line appears correctly
3. Claude runs a Task (foreground subagent) -- status line replaced by subagent activity indicator (expected)
4. Task completes, control returns to main conversation
5. Status line never reappears for the rest of the session

Expected behavior

Status line should resume displaying after the Task/subagent completes, since it updates on message changes (every 300ms).

Actual behavior

Status line disappears permanently once a Task runs. Only reappears on a new session.

Environment

• macOS 15
• Claude Code CLI (latest)
• Model: Claude Opus 4.5