CSV/Excel Merger Combine tabular files into one clean output without silently losing, duplicating, or corrupting rows. Workflow Copy this checklist and track progress: 1. Profile inputs. Run the bundled profiler first; it reports encoding, delimiter, rows, headers, candidate keys, and header overlap without changing anything: Excel files are profiled per sheet. Confirm with the user which sheets count if a workbook has more than one. 2. Choose the operation. This is the decision that most often goes wrong: - Append (stack) - same kind of records from different sources or periods (Jan + Feb ex…