Kernel API /api/file/readDir support for returning symbolic link information

[Zuoqiu-Yingyi]

• Please commit to the dev branch
• For contributing new features, please supplement and improve the corresponding user guide documents

• directory symlink: isDir: true, isSymlink: true
• directory normal: isDir: true, isSymlink: false
• file symlink: isDir: false, isSymlink: true
• file normal: isDir: false, isSymlink: false

[github-actions]

Your PR was set to target master, PRs should be target dev
The base branch of this PR has been automatically changed to dev, please check that there are no merge conflicts

[fenilgmehta]

Suggested change

	"isDir": info.IsDir(),
	"isDir": entry.IsDir(),

Why change from entry.IsDir() to info.IsDir() ?
entry.IsDir() / dir.IsDir() (where entry and dir are of type fs.DirEntry) is being used in kernel/util/file.go > IsDirRegularOrSymlink too.

[Zuoqiu-Yingyi]

// entry is a symlink to a dir
path := filepath.Join(dirPath, entry.Name())
info, err = os.Stat(path)

entry.IsDir() // return false
info.IsDir() // return true

[88250]

Guys, let's make sure the code here is ok:

[88250]

Oh, sorry, I missed the changes in file.go later, Zuoqiu has extracted a function IsSymlink(), it seems to be no problem.

[Zuoqiu-Yingyi]

Guys, let's make sure the code here is ok:

If this function's name is IsDirRegularOrSymlink, it's Ok.
If this function's name is IsDirRegularOrDirSymlink, it's not Ok.👀

[88250]

@Zuoqiu-Yingyi Thanks for the explanation, I get it, merge first.

@fenilgmehta If there is something we missed, please continue to add comments, thank you.