Port static filesystem ACL reads to security constructors

Replace resolved static File/Directory.GetAccessControl(path[, includeSections]) with the FileSecurity/DirectorySecurity constructor to which Framework forwards. Preserve explicit sections, the default Access|Owner|Group sections, argument nodes and evaluation order. Windows ACL support and access-control assemblies (System.IO.FileSystem.AccessControl on .NET Core 3.0) are required. Named arguments, instance/extension methods, setters, unresolved calls, discarded comments, lambda/query contexts and conditional snapshots stay unchanged. Individually available API port; no permissions or cross-platform policy is selected.