Comprehensive ARDL: Panel, Bootstrap and Fourier Methods // A unified framework for Autoregressive Distributed Lag (ARDL) modeling and cointegration analysis. Implements Panel ARDL with Pooled Mean Group (PMG), Mean Group (MG), and Dynamic Fixed Effects (DFE) estimators following Pesaran, Shin Smith (1999) doi:10.1002/jae.616. Provides bootstrap-based bounds testing per Pesaran, Shin Smith (2001) doi:10.1002/jae.616. Includes Quantile Nonlinear ARDL (QNARDL) combining distributional and asymmetric effects based on Shin, Yu Greenwood-Nimmo (2014) doi:10.1007/978-1-4899-8008-3_9, and Fourier ARDL for modeling smooth structural breaks following Enders Lee (2012) doi:10.1016/j.econlet.2012.05.019. Features include Augmented ARDL (AARDL) with deferred t and F tests, Multiple-Threshold NARDL for complex asymmetries, Rolling/Recursive ARDL for time- varying relationships, and Panel NARDL for nonlinear panel cointegration. All methods include comprehensive diagnostics, publication-ready outputs, and visualization tools.