ArWen 2.5.2

New

• Radiation is about 1.9x faster at the default column chunk, and the
  allocation estimate drops roughly 1.5 GB. Output is byte-identical on
  both cards it was measured on. Contributed by Roch.
• The chunk ladder flattened with the radiation workspace. gpuwm check
  against a 19.5 GiB budget now names one halving of the configured chunk
  where the same case used to have to walk back two.
• gpuwm fetch --source era5 writes era5-cds-retrieve.py beside the
  request document and prints the one command that runs it. The script
  resolves every path from its own location, so it produces the same
  files from any working directory and under any interpreter, including
  a WSL python3 reached from Windows.
• gpuwm fetch --source era5 --validate reports the delivered grid shape,
  spacing and corners, and fails a file whose grid falls short of the
  requested --area, naming the edge and the shortfall.
• gpuwm doctor checks that the directory holding the gpuwm console
  script is on PATH and prints the exact line that fixes it.

Fixed

• gpuwm downscale runs a full-physics child without
  --child-surface-from. The child's land identity and soil warm start
  are taken from the parent's own history frame. Previously the flag was
  mandatory and pointed at a file no command could produce for a
  config-driven parent, so a full-physics child of a [case_data] run
  was unreachable. The flag stays as the higher-fidelity route.
• gpuwm downscale --point writes the derived child config to
  <out>/child.toml, inside the run it describes.
• Static fields no longer depend on which source window a build read. On
  a geography source that wraps in x, two builds covering the same ground
  sampled the source at coordinates differing in their last bits, so a
  moving nest whose statics corridor crossed the wrap seam refused every
  relocation and wrote no frames after the first move. Measured after the
  fix: 3,519,936 cells compared per move, zero mismatches, two moves
  completed, 26 frames.