Changes in version 0.1.0                        

  - Initial version.
  - Native R implementations of the Triply RObust Panel (TROP) estimator
    of Athey, Imbens, Qu & Viviano (2026).
  - panel_compare() runs DID, SDID, SC, MC, TROP, gsynth and augsynth on
    one dataset and returns a common tidy ATT schema with shared plots.
  - trop_matrix() provides a matrix-in form whose results can be
    numerically compared with the official Python trop matrix-in
    signature for direct cross-checking; verified to match the reference
    to numerical tolerance on the weighted-TWFE special case.