Wire the VK Mini Apps ("голоса") rail end to end, reusing the intake engine. The
wallet.order endpoint branches by rail: a VK context opens a pending order
(provider vk) and returns its id, which the client passes to VKWebAppShowOrderBox.
VK's two-phase payment callback is verified at the gateway with the app protected
key (GATEWAY_VK_APP_SECRET) and proxied to a backend intake handler: get_item
returns the ordered pack's title and vote price; a chargeable order_status_change
credits the vk segment exactly once (the same Fund, idempotent on VK's own order
id) and records a succeeded event, so the dispatcher push refreshes the wallet.
Integration test for the VK order->credit path.
Ilia Denisov
3bb9f10fad