This issue requests adding a function to compute autocorrelation of missing values in the naniar package. The request references issue #45 by @MilesMcBain. To implement, examine existing helper functions in the package (e.g., in R/ folder) for pattern and style. The function should likely compute serial correlation of missingness indicators (0/1) along data frame rows or columns. No comments or PRs exist, so this is an open opportunity. Start by reviewing linked issue #45 for context.