weatherfeeder: split the former maximumdirect.net/weatherd project in two.

feedkit now contains a reusable core, while weatherfeeder is a concrete implementation that includes weather-specific functions.

internal/model/alert.go

@@ -0,0 +1,23 @@
+package model
+
+import "time"
+
+// Placeholder for NWS alerts (GeoJSON feature properties are rich).
+type WeatherAlert struct {
+	ID string
+
+	Event       string
+	Headline    string
+	Description string
+	Instruction string
+
+	Severity  string
+	Urgency   string
+	Certainty string
+
+	Sent      *time.Time
+	Effective *time.Time
+	Expires   *time.Time
+
+	Areas []string
+}