Update how RPCs are handled

The processor now takes three vars and joins them itself. message-queue uses a
single argument, with defaults, as it's a service we control.

processor/Cargo.toml

@@ -52,6 +52,7 @@ monero-serai = { path = "../coins/monero", features = ["multisig"], optional = t
 
 # Application
 log = "0.4"
+env_logger = "0.10"
 tokio = { version = "1", features = ["full"] }
 
 rocksdb = "0.21"