Payments/subscriptions support (#943)

* [wip] Payments/subscriptions support

* finish

* working payment flow

* finish subscriptions, lint, clippy, etc

* docker compose

src/util/webhook.rs

@@ -5,7 +5,6 @@ use crate::routes::ApiError;
 use chrono::{DateTime, Utc};
 use serde::Serialize;
 use sqlx::PgPool;
-use std::usize;
 
 #[derive(Serialize)]
 struct DiscordEmbed {