How to fill zeros before problem id in file name?

[SLKyrim]

Cannot find solution in Customize the Relative Folder and the File Name of the Problem File

💬 Questions

The format of my file name is

"filename": "${id}-${kebab-case-name}.${ext}"

Now I want ${id} to be four digits so that the files can be sorted by their IDs on my Github repo.
For example, I click "Show Problem" and generate a file named "1.两数之和.py" and I want it to be "0001.两数之和.py". How can I implement this setting?

[yihong0618]

See #582 maybe add later.