Instead of returning "malformed section" on trailing bytes or truncated
sections, attempt to return parsed results. This handles older HRRR
files (2019) that have padding bytes after the last section.
consume_bits would crash with a MatchError when the remaining
bitstring had fewer bits than the group width. Added a guard
clause to stop consuming when insufficient bits remain, matching
how wgrib2 handles trailing padding in packed data sections.
Eliminates the external wgrib2 C tool dependency that blocked HRRR
processing. Implements Lambert Conformal projection, simple packing
(Template 5.0), complex packing with spatial differencing (Template 5.3),
and GRIB2 section parsing — enough to extract point values from HRRR
grid data using only Elixir.
