The /path calculator showed "0 / 9 HRRR points" in production despite
the on-disk profile store being current. Root cause: profile_from_cell/2
treated the cell's :profile key as a wrapper sub-map and called
Map.put_new on it — but the :profile key actually holds the vertical
pressure-level LIST. Every point sample crashed with BadMapError, the
crash propagated as {:exit, _} through Task.async_stream, and the
consumer silently dropped all 9 results.
Fix: stop wrapping. Cells are already flat HrrrProfile-shaped maps;
just stamp lat/lon (from the caller, since cells don't carry their
own coords — those are the map key) and valid_time onto the cell.
Audit + log every other async error path so the next silent failure
isn't invisible:
- PathLive HRRR point lookup
- Propagation.point_forecast per-hour reads
- Viewshed ray crashes
- IemClient ASOS network fetches
- RtmaClient range-download tasks
- Recalibrator factor-vector batches (positive + negative samples)
- MapLive forecast preload tasks
- RoverLive station resolution
LiveViews already had handle_async/3 exit clauses with logging. The
gap was always in Task.async_stream consumers that wrote {:exit, _} -> []
without surfacing the reason.
Add the rule to CLAUDE.md and project memory so this never repeats.
Also fix a pre-existing skewt_svg.ex compiler warning where
@critical_label_min_dy was used before being defined.
Graham McIntire
418f6426e6