Background tasks don't stream output (--print mode buffers until completion)

Problem

When running background tasks via claude --print, output is buffered until the task completes. This makes it impossible to monitor long-running tasks in real-time.

Current Behavior

# Spawn background task
ct_run "Run E2E tests and fix failures"

# Check logs immediately - only see header
ct_logs task-xxx
# Output: Just the initial header, no streaming content

# Process tree shows active work (Playwright running)
pstree -p 761026
# Shows: claude -> npm exec @playwright -> node workers

# But logs don't update until task completes

Expected Behavior

Output should stream to the log file in real-time, allowing:

• Monitoring progress of long-running tasks
• Early detection of issues
• Understanding what the agent is currently doing

Reproduction

1. Start a background task: claude --print "Run all E2E tests"
2. Monitor the log file: tail -f ~/.claude-tasks/logs/task-xxx.log
3. Observe: No output streams until task completes

Environment

• Claude Code CLI
• Running via MCP server that spawns claude --print with detached stdio

Suggested Fix

Add a --stream flag or make --print stream by default when stdout is a pipe/file rather than TTY.

🤖 Generated with Claude Code