Migration v16 adds tasks.archived (default 0) + tasks.archived_at +
idx_tasks_archived. TaskRow extended with both fields; list_tasks and
list_subtasks default-filter archived rows; complete_subtask_and_check_parent
SELECT lists updated to round-trip the new columns. TaskListRow +
ImportSummary structs land in preparation for the task_lists CRUD
that part 2 wires up. All 61 existing tests still pass.
(SQL splitter is naive about ';' inside -- comments, so the v16
comment block was rewritten to avoid a bare semicolon mid-comment
that the splitter was treating as a statement boundary.)
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>