Separate controlled import data from

Separate controlled import data from spreadsheet text.

This synthetic export keeps all 5 records. Four formula-like strings receive an apostrophe prefix in a separate spreadsheet-safe copy. The numeric negative string -12.50 stays unchanged. The normalized export retains the original values for controlled software import.

Demonstration work for Clean Sheet Sprint; no client result is claimed. The original file and issue log document exactly what changed.