APPLYVARLABELS: Stata module to apply variable labels to the data in memory from a two-column (Variable, Label) crosswalk

Label the variables in memory from an Excel workbook or a delimited file that lists each variable name beside the label it should carry. Solves the Statalist problem (thread 1768839) where a levelsof/tokenize loop puts the wrong label on the wrong variable because levelsof sorts the labels alphabetically. applyvarlabels reads the crosswalk in row order and matches every label to its variable BY NAME, never by position. It writes a capture-guarded relabel do-file (a variable named in the crosswalk but absent from the data is skipped, not an error), runs it to apply the labels, and prints an inventory of what did not line up: crosswalk rows with no such variable, and variables in memory with no crosswalk row. The data in memory are never sorted, dropped, or reordered - the crosswalk is read in its own frame, so nothing changes but the variable labels themselves. The generated do-file is a keepable, rerunnable artifact (see dofile()). Reads .xlsx/.xls and .csv/.tsv/.txt; nocase matches names ignoring case; norun writes the relabel do-file without applying it.