bug: python operator.list with start_after does not work for local file system

### Describe the bug

Open dal operator list method with start_after arugment works fine with s3 but not with local file system. It always list all the files from the path. Eg. code given below.

```
operator = Operator("fs", root="tmp")
files = list(operator.list("", start_after = files[-1].path))
```

files has all entire list of files from the path in case of local file system. In case of s3, it only gives the new file.
Please help me resolve this issue

### Steps to Reproduce

Explained in the bug details

### Expected Behavior

The method should list only the new files in the path.

### Additional Context

_No response_

### Are you willing to submit a PR to fix this bug?

- [ ] Yes, I would like to submit a PR.

Start at the Operator.list entry point and reproduce the difference between the local filesystem and S3 implementations with start_after. Compare the local filesystem behavior against the expected result: return only files after the supplied path, rather than the entire directory listing.

Written by the indexing model from the issue text.