'ggplot2'-Based Visualization for 'PanelMatch' (Imai, Kim, Wang 2023) Results // Provides 'ggplot2'-based plotting functions for 'PanelMatch' (Imai, Kim, Wang (2023) doi:10.1111/ajps.12685) results. Tidy-and-plot function pairs for three 'PanelMatch' outputs: treatment effect estimates (PanelEstimate()), placebo test diagnostics (placebo_test()), and covariate balance checks (get_covariate_balance()). Supports multiple models, significance indicators, faceted balance grids, and full 'ggplot2' extensibility.