time.strftime("%Z") prints the .NET zone display name ("Eastern Daylight Time"), not python's abbreviation ("EDT")

[antonsynd]

Found by /verify-implementation plan-0ca7b7 (2026-09-26), measured @ 61bf20f with the built sharpyc; pre-existing at BASE acd1d40 unless noted.

import time; print(time.strftime("%Z")): python3 prints EDT and Sharpy prints Eastern Daylight Time (host America/New_York). Since 0eca2b3, time.strftime goes through Strftime.cs's platform pass with the host zone for %z/%Z. The %Z name comes from TimeZoneInfo.DaylightName/StandardName, which is the Windows-style display name, while python uses libc tzname (the abbreviation). Also affects time.tzname if it exists. The IANA abbreviation isn't exposed by TimeZoneInfo, so this needs a design choice (the libc tzname via interop, or a tzdb abbreviation table).

[antonsynd]

Batching 2026-09-30 @ db8e05b — charter .claude/plans/remediation-round-2026-09-20-batching.md §3.30, P35 — culture invariance + datetime fidelity (order N4).

Ruling R-DB (owner, 2026-09-30): %Z prints the abbreviation via libc strftime/tzname (interop) on Unix; the .NET display name plus a docs/deviations.yaml row on Windows. Rejected: a deviation row everywhere (strftime is COMPARED under R-CL). Lane / reach: silent-wrong · program. Also covers time.tzname if present. Class tracker: #2056. No seam hypothesis — the plan measures the seam.