[Feature Request] add full time mode in Humanize

```js
dayjs.duration(100, "s").humanize(); --> // 2 分钟
```

full time mode

``` js
dayjs.duration(100, "s").humanize( {full:true} ); --> // 1分40秒
```

Start at the duration humanize() entry point and inspect how a 100-second duration is currently converted to a rounded unit. Define the full-time option's expected output from the example, then verify that the default behavior remains unchanged and that the new option produces 1分40秒.

Written by the indexing model from the issue text.