A script to check the current illumination level of a selected Token.
Basic usage: !checklight with a token selected
checkLightLevel.litBy(tokenOrId)
Returns a LitBy object:
/*
* @typedef {object} LitBy
* @property {?boolean} bright - token is lit by bright light, null on error
* @property {?array} dim - dim light emitters found to be illuminating selected token, null on error
* @property {?float} daylight - token is in <float between 0 and 1> daylight, false on no daylight, null on error
* @property {?float} total - total light multiplier from adding all sources, max 1, null on error
* @property {?boolean} partial - if true, no source of light is completely illuminating the token's area
* @property {?string} err - error message, only on error
*
* @param {string | object} tokenOrTokenId - Roll20 Token object, or token UID string
* @returns {LitBy}
*/