routie dev init since i didn't adhere to any proper guidance up until now

frontend/node_modules/eslint/lib/rules/utils/unicode/is-combining-character.js

@@ -0,0 +1,13 @@
+/**
+ * @author Toru Nagashima <https://github.com/mysticatea>
+ */
+"use strict";
+
+/**
+ * Check whether a given character is a combining mark or not.
+ * @param {number} codePoint The character code to check.
+ * @returns {boolean} `true` if the character belongs to the category, any of `Mc`, `Me`, and `Mn`.
+ */
+module.exports = function isCombiningCharacter(codePoint) {
+	return /^[\p{Mc}\p{Me}\p{Mn}]$/u.test(String.fromCodePoint(codePoint));
+};