Implement support for NWS weather stories

docs/internal/briefing.md

@@ -24,6 +24,8 @@ Outputs:
   object for Daily, 3-Day, Weekend, or Storm Report
 - optional `currentConditions` prompt context from normalized
   `/conditions/current` data when available
+- optional structured `weatherStory` context on report-specific briefing
+  objects when `/weatherstories/latest` is available
 - optional JSON file written by `briefing.Save`
 
 ## Boundaries

docs/internal/prompt-input.md

@@ -19,8 +19,8 @@ Outputs:
 - `promptinput.Package` containing schema version, RunID, report metadata,
   briefing content, Recent Changes, and source warnings. Briefing content
   includes configured location context, current conditions when available,
-  discussion key messages, and short/long-term AFD narratives when the Weather
-  API provides them.
+  structured weather story context when available, discussion key messages, and
+  short/long-term AFD narratives when the Weather API provides them.
 - report metadata includes `currentLocalDate`, the generation date formatted as
   `YYYY-MM-DD` in the effective report timezone.
 - optional JSON file written by `promptinput.Save`

docs/internal/weather-data.md

@@ -7,7 +7,7 @@ This document describes Weather API ingestion into `forecast.Bundle`.
 `internal/adapters/weatherapi` fetches normalized weather data from one
 configured Weather API endpoint and assembles the bundle consumed by forecast
 derivation and briefing builders. Briefing builders expose normalized current
-conditions as prompt context when `/conditions/current` is available.
+conditions and weather story context when those sources are available.
 
 ## Inputs And Outputs
 
@@ -20,9 +20,9 @@ Inputs:
 Outputs:
 
 - `forecast.Bundle` with observation, current conditions, hourly forecast,
-  narrative forecast, active alerts, discussion, source records, and source
-  warnings
-- stub source records for daily forecast and weather story source slots
+  narrative forecast, active alerts, discussion, latest weather story, source
+  records, and source warnings
+- stub source record for the daily forecast source slot
 - optional saved bundle JSON through app fetch helpers
 
 ## Boundaries