dayjs Adding weeks in duration plugin is broken

Describe the bug

I haven't upgraded since 1.11.7 because of various bugs, and this is the big one now:

Sample code:

const dayjs = require('dayjs')
dayjs.extend(require('dayjs/plugin/duration'))

const today = dayjs()
const twoWeeksFromNow = dayjs().add(dayjs.duration({weeks:2}))

console.log({today,twoWeeksFromNow})

(I have tried both week and weeks)

Here is what I get in 1.11.10:

❯ node ./dayjs-bug.js
{
  today: M {
    '$L': 'en',
    '$d': 2023-10-16T17:38:24.875Z,
    '$y': 2023,
    '$M': 9,
    '$D': 16,
    '$W': 1,
    '$H': 13,
    '$m': 38,
    '$s': 24,
    '$ms': 875,
    '$x': {},
    '$isDayjsObject': true
  },
  twoWeeksFromNow: M {
    '$L': 'en',
    '$d': 2023-10-16T17:38:24.875Z,
    '$y': 2023,
    '$M': 9,
    '$D': 16,
    '$W': 1,
    '$H': 13,
    '$m': 38,
    '$s': 24,
    '$ms': 875,
    '$x': {},
    '$isDayjsObject': true
  }
}

Expected behavior

I expect this calculation to happen similarly to how it does in 1.11.7:

❯ node ./dayjs-bug.js
{
  today: M {
    '$L': 'en',
    '$d': 2023-10-16T17:41:20.524Z,
    '$x': {},
    '$y': 2023,
    '$M': 9,
    '$D': 16,
    '$W': 1,
    '$H': 13,
    '$m': 41,
    '$s': 20,
    '$ms': 524
  },
  twoWeeksFromNow: M {
    '$L': 'en',
    '$d': 2023-10-30T17:41:20.524Z,
    '$x': {},
    '$y': 2023,
    '$M': 9,
    '$D': 30,
    '$W': 1,
    '$H': 13,
    '$m': 41,
    '$s': 20,
    '$ms': 524
  }
}

Information