The /weather map now shows HRRR-derived data wherever HRRR has
coverage and falls back to HRDPS-derived data for Canadian cells
outside HRRR's bbox. North of the 49°N HRRR-coverage line the map
stays populated instead of going blank.
Rust:
- weather_scalar_file::dir_for_hrdps + write_atomic_hrdps land HRDPS
scalar chunks at `<vt>.hrdps/` so HRRR's `<vt>/` write isn't
clobbered. The HRRR writer wipes its dir before each write — both
sources need their own dir to coexist.
- pipeline::run_chain_step_hrdps now derives a ScalarRow for each
scored cell (same derive_row that HRRR uses; same wire format) and
writes them via write_atomic_hrdps alongside the .hrdps.prop score
files.
Elixir:
- ScalarFile.dir_for_hrdps + read_bounds + read_point + exists? all
walk both `<vt>/` (HRRR) and `<vt>.hrdps/` (HRDPS). read_bounds
concatenates with HRRR-precedence on overlap (defensive — Rust
pipeline doesn't write HRRR-overlap cells, but cheap to enforce).
- Weather.weather_grid_at unchanged: it routes through ScalarFile,
which now transparently returns the union. GridCache stays
per-valid_time so a single cache entry holds both regions.
Tests cover four scenarios: HRRR-only, HRDPS-only, both-present
union, and HRRR-precedence on the same cell.
Graham McIntire
3607a915ba