Refactor BTCPay service and API, add lightning balance

.env.test

@@ -2,13 +2,14 @@ PRIMARY_DOMAIN=kosmos.org
 
 REDIS_URL='redis://localhost:6379/0'
 
+BTCPAY_API_URL='http://btcpay.example.com/api/v1'
+BTCPAY_STORE_ID='123456'
+
 DISCOURSE_PUBLIC_URL='http://discourse.example.com'
 DISCOURSE_CONNECT_SECRET='discourse_connect_ftw'
 
 EJABBERD_API_URL='http://xmpp.example.com/api'
 
-BTCPAY_API_URL='http://btcpay.example.com/api/v1'
-
 LNDHUB_API_URL='http://localhost:3026'
 LNDHUB_PUBLIC_URL='https://lndhub.kosmos.org'
 LNDHUB_PUBLIC_KEY='024cd3be18617f39cf645851e3ba63f51fc13f0bb09e3bb25e6fd4de556486d946'