These functions are internal building blocks used by SignalProcessingUltra:
alignSpectra_landmark_cpp: wrapper that applies landmark matching/warping per spectrum.
cpp_match_anchors: Rcpp function for greedy 1:1 matching between spectrum peaks and reference anchors.
cpp_warp_mz_piecewise: Rcpp function for piecewise-linear warping of a mass axis.
They are not part of the user-facing API.