Fix issues #1, #3, #5: misc improvements

- #5: Unwrap _brand.yml for Quarto 1.9+ compatibility (remove top-level
  brand: wrapper so meta/logo/color/typography are at the top level)
- #1: Add quiet parameter to na_sum() to suppress warnings in loops/pipelines
- #3: Add beep() function for CLI beep, desktop notifications, and webhook
  alerts (supports type=beep|notify|webhook|all)

R/utils.R

@@ -149,6 +149,9 @@ race_short_names <- function(x) {
 #' Sum a numeric that contains missing values and ignore missing values
 #'
 #' @param x a numeric vector
+#' @param quiet Logical. If `TRUE` (default `FALSE`), suppress the warning
+#'   message. Useful when calling `na_sum()` inside a loop or `dplyr` pipeline
+#'   where the message would be emitted repeatedly.
 #'
 #' @return the sum, ignoring any missing values
 #' @export
@@ -156,9 +159,12 @@ race_short_names <- function(x) {
 #' @examples
 #' x <- c(2, NA, 4, 9)
 #' na_sum(x) # 15
-na_sum <- function(x) {
+#' na_sum(x, quiet = TRUE) # 15 (no message)
+na_sum <- function(x, quiet = FALSE) {
   stopifnot(is.numeric(x))
-  message("Taking a sum with missing values equal to 0, be careful!")
+  if (!quiet) {
+    message("Taking a sum with missing values equal to 0, be careful!")
+  }
   x <- na_zero(x)
   return(sum(x))
 }