Ability for @std/fs/walk to ignore or handle PermissionDenied errors

[rameshvenk]

Is your feature request related to a problem? Please describe.

The @std/fs/walk has an issue where if it encounters a directory that it does not have read permissions, it errors with a PermissionDenied: Permission denied (os error 13)
Describe the solution you'd like

Add another option to the WalkOptions type to be able to specify a handler which can handle this error and rethrow it or ignore it, or, an option to be able to ignore this error and continue (the first would be preferred).

Describe alternatives you've considered

An alternative is to re-write this feature using a generator function which seems to work, but since this feature is already available in the standard library, it would be useful to add an option to ignore or handle directories and files that it does not have permission to read

Test script

import { walk } from "jsr:@std/fs/walk";

try {
  for await (const dirEntry of walk("/etc/")) {
    console.log("Recursive walking:", dirEntry.name);
  }

} catch (err) {
  console.error(err);
}

Produces in my Macbook
PermissionDenied: Permission denied (os error 13): readdir '/etc/cups/certs'