Initial release.
caged_available() lists the reference months published
on the PDET/MTE FTP server, with folder modification dates.caged_download() fetches the MOV,
FOR and EXC archives of one or more months
into an idempotent local cache (caged_cache_dir(),
caged_cache_list(), caged_cache_clear()).caged_read() stream-reads a national .7z
archive, filtering by state and selecting columns chunk by chunk, with
normalised column names and typed codes; caged_fetch()
combines download and read for several months.caged_balance() consolidates admissions, separations
and net balance by competenciamov, inverting the sign of
exclusion records.caged_layout() documents the 30 columns of the official
record layout.inst/extdata allow every reading
function to be tried offline.