normalizeSizes = (value, defaultSizeTypes) => {
	if (typeof value === "number") {
		/** @type {Record<string, number>} */
		const o = {};
		for (const sizeType of defaultSizeTypes) o[sizeType] = value;
		return o;
	} else if (typeof value === "object" && value !== null) {
		return { ...value };
	}
	return {};
}
@param {OptimizationSplitChunksSizes | undefined} value the sizes
@param {string[]} defaultSizeTypes the default size types
@returns {SplitChunksSizes} normalized representation