run `fnm list` and convert output to PowerShell custom objects

List-FnmVersions.ps1

fnm list | Select-String -Pattern '(?in)^\* (?<version>[\S+]+)(?<label>(\s[^,\s]+)(,\s*\S+)?)?' |
Select-Object -ExpandProperty Matches |
ForEach-Object {
  $h = @{}
  foreach ($g in $_.Groups) {
    if (-not $g.Success -or $g.Name -eq '0') {
       continue;
    }
    $h.Add($g.Name, $g.Value)
  }
  [pscustomobject]$h
}