Function ensureUniqueHtmlTemplate

lib/config/defaults.js:1694–1695

(template)

	 * @returns {string} same template, or `[name].html` if it has no per-module placeholder
	 */
	const ensureUniqueHtmlTemplate = (template) =>
		HAS_PATH_PLACEHOLDER_REGEXP.test(template) ? template : "[name].html";
	F(output, "htmlFilename", () => {
		const filename =
			/** @type {NonNullable<Output["htmlFilename"]>} */