The real LA leak was a zone-only advisory with no polygon and no centroid —
the fail-open gate kept it. Now NWS attaches the full GeoJSON alert geometry
(Polygon/MultiPolygon) to the event, and the coverage gate drops weather
alerts it cannot locate (fail-closed, matching Central), while staying
fail-open for other categories. Removes the old buggy adapter-level
_in_coverage heuristic (the gate supersedes it).
Co-authored-by: Matt Johnson <mj@k7zvx.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Phase 2c: nws derives its area= state filter from the bbox (states it
overlaps) AND drops alerts whose centroid falls outside the box for precise
scoping; traffic samples a 3x3 grid of flow points across the bbox instead
of hand-listed corridors. Coverage governs when set; each adapter's own
config is the fallback.
Co-authored-by: Matt Johnson <mj@k7zvx.com>
Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>