Parse the language and daily/<date>/<subfolder> location from a analysis/daily/<date>/<subfolder>/executive-brief_<lang>.md path.
daily/<date>/<subfolder>
analysis/daily/<date>/<subfolder>/executive-brief_<lang>.md
Returns null for any path that doesn't fit the canonical layout, so the caller can skip non-brief files without crashing.
null
Parse the language and
daily/<date>/<subfolder>location from aanalysis/daily/<date>/<subfolder>/executive-brief_<lang>.mdpath.Returns
nullfor any path that doesn't fit the canonical layout, so the caller can skip non-brief files without crashing.