GeoLibre tile + service proxy.
  Passthrough: /opm/<dataset>/<z>/<x>/<y>.png
    Datasets: mars-mola-color-noshade, mars-viking-mdim21, mars-hillshade, mars-mola-color, mars-mola-gray, moon-hillshaded-albedo
  Reprojected WMS: /wms/<dataset>/<z>/<x>/<y>.png
    Datasets: mercury-messenger-color, mercury-messenger, venus-magellan, venus-magellan-color, io-galileo-color, europa-galileo-voyager, ganymede-galileo-voyager, callisto-galileo-voyager, titan-cassini, titan-hisar, pluto-mosaic, pluto-color, charon-mosaic
  OpenAerialMap search: /oam/meta?bbox=...&limit=...
  CKAN search: /ckan/search?q=...&rows=...&start=...
  Source Cooperative metadata: /source-coop/products/... , /source-coop/feed
  GitHub repository file: /github-raw?url=https://github.com/.../raw/...
  PMTiles range proxy: /pmtiles/<name>.pmtiles (Range header required)