v0.9.0 — data boards

Requires a TaskLite server from 2026-09-06 for the new behaviour; older servers ignore kind.

Added

• Data boards. create_board takes kind: "tasks" (default) also gives the board the built-in task columns; "data" creates a plain table with only the columns you add. build_backend boards default to "data": a backend's tables are customers, orders and payments, not to-dos. Rows of a data board come back from the App API without status and priority.
• Relation values from the App API always carry relatedItems: [{ id, title }] next to relatedItemIds, so a frontend shows a name without a second request.