Fix random arbitrary shutdown by using exceptions

src/main/kotlin/mdnet/base/ServerManager.kt

@@ -5,6 +5,7 @@ import com.fasterxml.jackson.databind.ObjectMapper
 import com.fasterxml.jackson.databind.SerializationFeature
 import com.fasterxml.jackson.module.kotlin.jacksonObjectMapper
 import com.fasterxml.jackson.module.kotlin.readValue
+import java.lang.RuntimeException
 import java.time.Instant
 import java.util.Collections
 import java.util.LinkedHashMap
@@ -145,7 +146,7 @@ class ServerManager(serverSettings: ServerSettings, devSettings: DevSettings, ma
                     }
                 }
             } catch (e: Exception) {
-                LOGGER.warn(e) { "Main loop failed" }
+                LOGGER.error(e) { "Main loop failed" }
             }
         }, 15, 15, TimeUnit.SECONDS)
 
@@ -199,7 +200,8 @@ class ServerManager(serverSettings: ServerSettings, devSettings: DevSettings, ma
         val state = this.state as Uninitialized
 
         val remoteSettings = serverHandler.loginToControl()
-            ?: Main.dieWithError("Failed to get a login response from server - check API secret for validity")
+            ?: throw RuntimeException("Failed to get a login response from server")
+
         val server = getServer(cache, database, remoteSettings, state.serverSettings, statistics, isHandled).start()
 
         if (remoteSettings.latestBuild > Constants.CLIENT_BUILD) {