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.
Add the public /pay/robokassa/result callback proxy (rate-limited; forwards the
provider's form parameters to the backend intake, the single writer, and echoes
its "OK<InvId>" back to Robokassa) and the /pay/robokassa/{success,fail}
browser-return redirects into the app. Route /pay/* to the gateway in the
contour Caddyfile so the callback reaches the edge, not the landing catch-all.
The backend intake now returns the echo body as JSON for the gateway to relay.
Wire the Robokassa direct rail into the backend transport. POST
/api/v1/user/wallet/order (walletGate + a D36 confirmed-email gate for the
direct rail) opens a pending order and returns the signed Robokassa payment
URL. The internal, gateway-only /payments/robokassa/result endpoint verifies
the Result signature, credits the matched order exactly once via Fund (honoured
even if expired), records a succeeded payment event, and answers Robokassa's
"OK<InvId>". Add the Robokassa env config, an account HasConfirmedEmail check
(D36), the payment_events writer, and a periodic pending-order reaper. The
routes register only when a Robokassa merchant login is configured.
Ilia Denisov