BC year formatted as 'YYYY' abnormally

[Jevin0]

Describe the bug
If you use 'dayjs('-000001').year()', you can get the real '-1' year. But if you use the format method, the internal padStart will automatically fill in 0. I'm not sure if this is a special scenario? Does it need special processing?

dayjs('-000001').format('YYYY') 
//  '00-1'

dayjs('-000010').format('YYYY') 
//  '0-10'

dayjs('-000100').format('YYYY')
// '-100'

Expected behavior

dayjs('-000001').format('YYYY') 
// '-0001'

dayjs('-000010').format('YYYY') 
//  '-0010'

dayjs('-000100').format('YYYY')
// '-0100'

Information

• Day.js Version [e.g. v1.11.13]
• OS: [e.g. windows]
• Browser [e.g. chrome 128]
• Time zone: utc