Per-task checklist backend: subtasks table with CASCADE delete,
SubtaskEntity + SubtaskRepository (connection-per-op, async), DI
registration in App and Worker, TaskRunner composes a '## Sub-Tasks'
markdown block into the Claude prompt when subtasks exist.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Create .slnx with five projects, wire references (App->Ui->Data,
Worker->Data, Tests->Worker+Data), install Avalonia/MVVM/SignalR.Client/
Sqlite/Hosting packages, and add schema.sql per docs/plan.md.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>