Audit pass found two real issues (most agent-flagged items were false
positives — the hrrr_native_profiles composite index exists,
pwat_mm/bl_depth_m are already in the path conditions map, and the
/1.0 in MechanismClassifier is the standard Elixir int→float coerce).
1. Path calculator's 9-point HRRR sampling was running sequentially,
~9× the latency of a single query. Task.async_stream with
max_concurrency: 9 makes them concurrent so path calc pays roughly
one query's worth of time instead of nine.
2. MechanismClassifyWorker's meteor-shower window used hardcoded 2024
peak dates with `%{date | year: peak.year}` projection. That broke
across year boundaries — a Dec 30 contact couldn't match a Jan 4
Quadrantids peak even in-range of the ±3 day window. Switched to
{month, day} tuples and check the peak projected onto year N-1, N,
N+1 so the window works correctly near Dec 31 / Jan 1.
Graham McIntire
2874e6a93b