acee4f25c7
Locks the #67193 invariants: localized PowerShell error bytes survive decode_console_bytes / read_decoded_line (including CP1252-only 0x91/0x92 punctuation), cached .ps1 files get a single UTF-8 BOM for Windows PowerShell 5.1 -File, .sh stays BOM-less, and mutable branch caches plan a refresh with stale-cache fallback.