Add price/currency params to create_place, create_and_assign_place,
create_place_accommodation (passed through to createPlace which already
persists them). Add price/budget_category to create_transport and
create_reservation: price is written to metadata.price (shown on the
booking) and a linked budget_items row is created via a new
linkBudgetItemToReservation helper in budgetService (also used to
de-duplicate the existing route-level logic in routes/reservations.ts).
Fixes#1031
Add reordering support for budget categories and line items within
categories. Changes persist via new DB table (budget_category_order)
and existing sort_order column. Live sync via WebSocket budget:reordered
event. Use Map instead of plain objects for category grouping to
preserve insertion order with numeric category names.
jubnl