Golden Gate scene: federal data sources and public-domain notices

The terrain, bathymetry, water maps and ground imagery in terrain/ were built by the
Golden Gate terrain pipeline (golden-gate-scene/terrain, round 2, accepted 2026-09-29)
entirely from US federal agency data. Its REPORT.md and sources.json record every download.

Sources
- NOAA NCEI CUDEM ninth-arc-second topobathy (2014), nine raster tiles: continuous land and bay
  floor, shoreline mask and water depth. NAD83 + NAVD88 (EPSG:5498).
  https://coast.noaa.gov/htdata/raster2/elevation/NCEI_ninth_Topobathy_2014_8483/CA/index.html
- USGS 3DEP elevation ImageServer, four clipped exports: lidar-derived near-ring land relief
  ("USGS 1 Meter 10 x54y419 CA_SanFrancisco_B23" at the bridge).
  https://elevation.nationalmap.gov/arcgis/rest/services/3DEPElevation/ImageServer
- USDA NAIP through the USGS NAIP ImageServer, twelve clipped exports: ground colour.
  https://imagery.nationalmap.gov/arcgis/rest/services/USGSNAIPImagery/ImageServer
- NOAA NGS control marks HT3032 (south tower), HT3028 (north tower), HT3034 and HT3070, and the
  NOAA CO-OPS datums of tide station 9414290 (San Francisco/Presidio): survey frame and vertical datum.
  https://geodesy.noaa.gov/cgi-bin/ds_mark.prl?PidBox=HT3032
  https://geodesy.noaa.gov/cgi-bin/ds_mark.prl?PidBox=HT3028
  https://api.tidesandcurrents.noaa.gov/mdapi/prod/webapi/stations/9414290/datums.json?units=metric

Public-domain notices (as quoted in the terrain REPORT.md)
- USGS: "Map services and data downloaded from The National Map are free and in the public domain."
  https://www.usgs.gov/faqs/what-are-terms-uselicensing-map-services-and-data-national-map
- NOAA: "The information on government web pages is in the public domain unless specifically
  annotated otherwise (copyright may be held elsewhere) and may therefore be used freely by the public."
  https://sos.noaa.gov/copyright/

No Google, Apple, Bing, Mapbox, Esri basemap or OpenStreetMap data is included.