Implements discrete curvature estimation for ordered planar point
    sequences using circumcenter geometry on consecutive triplets, exposed
    through compiled C plus plus (C++) code via 'Rcpp' for speed and numerical
    robustness. The package is useful for objective elbow detection in
    multivariate workflows, especially principal component analysis (PCA), where
    selecting the number of retained components can be subjective. It provides a
    'shiny' interface that supports upload of raw datasets or explained-variance
    tables, computes Kaiser-Meyer-Olkin (KMO) sampling-adequacy diagnostics,
    evaluates individual and cumulative variance curves, and reports curvature-
    based decision rules (m* and m**) with visual summaries for reproducible
    component-selection decisions. 
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