Refactor billing module

backend/src/lib.rs

@@ -1,5 +1,6 @@
 pub mod api;
 pub mod billing;
+pub mod bitcoin;
 pub mod cipher;
 pub mod command;
 pub mod infra;
@@ -7,3 +8,4 @@ pub mod models;
 pub mod pool;
 pub mod query;
 pub mod robot;
+pub mod stripe;