Since earned_time 0.8.0 each tutor credit row carries detail.minutes, so
counting rows against 4 hid the block after 4 credited minutes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YADHKXzZhhePzQ2rNoXFcK