Promote rfx_beta_draws to consistent array dimensions in predict.bcf

Ensure rfx_beta_draws has consistent dimensions when there's one rfx term.

Author: jaredsmurray

R/bcf.R

@@ -3162,6 +3162,11 @@ predict.bcfmodel <- function(
     rfx_beta_draws <- rfx_param_list$beta_samples *
       object$model_params$outcome_scale
 
+    # Promote to an array with consistent dimensions when there's one rfx term
+    if (length(dim(rfx_beta_draws)) == 2) {
+      dim(rfx_beta_draws) <- c(1, dim(rfx_beta_draws))
+    }
+
     # Construct a matrix with the appropriate group random effects arranged for each observation
     rfx_predictions_raw <- array(
       NA,