type DateWindow struct {
Days *int `json:"days,omitempty" jsonschema:"rolling window in days (default 90, max 365)"`
DateFrom string `json:"date_from,omitempty" jsonschema:"window start YYYY-MM-DD (overrides days)"`
DateTo string `json:"date_to,omitempty" jsonschema:"window end YYYY-MM-DD"`
}
type StationCity struct {
StationID string `json:"station_id,omitempty" jsonschema:"ICAO station id e.g. KLAX"`
City string `json:"city,omitempty" jsonschema:"city name (resolves to station)"`
}