Can't you just use add = c("mean_ci", "jitter")?
From Line plot — ggline • ggpubr
add
character vector for adding another plot element (e.g.: dot plot or error bars). Allowed values are one or the combination of: "none", "dotplot", "jitter", "boxplot", "point", "mean", "mean_se", "mean_sd", "mean_ci", "mean_range", "median", "median_iqr", "median_hilow", "median_q1q3", "median_mad", "median_range"; see ?desc_statby for more details.
Then when you run ?desc_statby is says it is a 95% CI on the mean.