Changes in version 0.1.0                        

  - Added a validated, dependency-light public API.
  - Added high-level analyze_incrementality() workflow.
  - Added Student's t and reproducible percentile-bootstrap intervals.
  - Added backward-compatible wrappers for the original API.
  - Added a complete vignette, examples, and testthat test suite.
  - Corrected the legacy confidence-interval calculation.