RED: seven Unicode regressions reproduced under Windows cp1252 and Linux ASCII with UTF-8 mode disabled. GREEN: Windows 91 passed with 5 platform skips; Linux ASCII 96 passed. Nine offline Unicode cases cover file, temporary YAML, prompt and all four CLI capture boundaries without model calls. Changed functions have 84.7% line coverage, each exceeds 80%; all 13 changed IO sites execute. Pi/catalog parity checks pass.
(cherry picked from commit 642cb0d512)