refactor: rename functions (#4655)

returnClientError => throwClientException
returnServerError => throwServerException

New convenience function: throwRateLimitException

Old functions are kept but deprecated.

bridges/FunkBridge.php

@@ -40,7 +40,7 @@ class FunkBridge extends BridgeAbstract
                 }
                 break;
             default:
-                returnServerError('Unknown context!');
+                throwServerException('Unknown context!');
         }
     }