Feature Request: Duration Plugin for Time Durations

Feature Request: Duration Plugin for Time Durations: a task in LegoFlow-SWE (Harbor dataset). Problem dayjs currently lacks a built-in way to represent, create, and manipulate time durations (e.g., “2 hours 30 minutes”). Users migrating from moment.js expect a duration API that supports flexible…

The task

**Problem** dayjs currently lacks a built-in way to represent, create, and manipulate time durations (e.g., “2 hours 30 minutes”). Users migrating from moment.js expect a `duration` API that supports flexible input, ISO 8601 parsing, arithmetic, humanization, and output formatting. Without this plugin, dayjs cannot…

Part of Lego-X/LegoFlow-SWE.