Restructure repo layout and document conventions

Move legacy systemscripts into scripts/display and scripts/setup.
Rehome stray top-level tools into their domain folders.
Archive narrow experiments and outdated codegrab leftovers.
Remove empty legacy directories and stale root files.
Expand macOS metadata ignores and update the README with the refined repository structure.

tools/forensics/mailunpack

@@ -0,0 +1,6 @@
+#!/bin/bash
+current_dir=$(pwd)
+mail_fail=$(readlink -f "${1}")
+filename=$(basename "${mail_fail}")
+file_dir=$(dirname "${mail_fail}")
+docker run -it --rm --user=`id -u` --net=none -v "${current_dir}:/home/nonroot/" -v "${file_dir}:/data:ro" tabledevil/file-analysis munpack -t "/data/${filename}"