Stable id written into the map's metadata channel. Keep it short — it is stored per owned cell.
Territory tint. Fills use it at fillOpacity; borders at full strength unless borderColor overrides.
OptionalborderBorder line color. Defaults to color.
A claimable faction: the owner ids stored per cell are these
idstrings. Fully JSON-serializable, so a faction roster rides through a.hexpackmanifest or a game save next to the map.