fix: variable connection with sqlx

Author: bennyhodl

.env.sample

@@ -4,8 +4,12 @@ POSTGRES_PASS=dlcdevkit
 POSTGRES_HOST=localhost:5432
 POSTGRES_DB=ddk
 DATABASE_URL=postgres://dlcdevkit:dlcdevkit@localhost:5432/ddk
+# Max size of the Postgres connection pool. Defaults to 5; raise to 20+ for production.
+DATABASE_MAX_CONNECTIONS=5
 
 ESPLORA_HOST=http://localhost:30000
+# Esplora request timeout in seconds. Defaults to 5.
+ESPLORA_TIMEOUT_SECONDS=5
 
 BITCOIND_USER=dlcdevkit
 BITCOIND_PASS=dlcdevkit