Use it now
Two new settings.json fields, timeFormat and timeZone, control how times are rendered in the UI.
Two new settings.json fields control how times render in the UI. timeFormat accepts auto, 12-hour, 24-hour, 24-hour-utc, or a strftime-style pattern, and timeZone accepts an IANA zone name, falling back to the system zone if the value isn't recognized.
Names in the bundletimeFormattimeZone24-hour-utc
Two sources agreeTwo things we can check say the same as this entry.
Anthropic's release notes agree
Added "Time format" (timeFormat) and timeZone settings: 12-hour, 24-hour, 24-hour UTC, or a strftime pattern for the turn-end clock and…
The name it cites is new in this build
New in this build: timeFormat