xiacf 0.5.0

• FWER Control: Implemented strict Family-Wise Error Rate (‘FWER’) control via Max-statistic across all core functions (xi_acf, xi_ccf, xi_matrix).
• Performance: Refactored core engines using C++ (RcppArmadillo) for MIAAFT and IAAFT surrogate generation, significantly improving computational speed.
• Visualization: Enhanced autoplot methods to produce publication-ready ggplot2 charts utilizing base R expression() for native math rendering.
• Compatibility: Improved backward compatibility to smoothly transition legacy sig_level = 0.95 (confidence level) inputs to significance levels, and systematically deprecated older functions with proper warnings.

xiacf 0.4.1

• Fixed a potential C++ RNG synchronization issue by delegating RNG state management entirely to Rcpp::RNGScope.