Initialisation

Added the packages and files for the backend server

node_modules/graphql/jsutils/keyMap.mjs

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+/**
+ * Creates a keyed JS object from an array, given a function to produce the keys
+ * for each value in the array.
+ *
+ * This provides a convenient lookup for the array items if the key function
+ * produces unique results.
+ * ```ts
+ * const phoneBook = [
+ *   { name: 'Jon', num: '555-1234' },
+ *   { name: 'Jenny', num: '867-5309' }
+ * ]
+ *
+ * const entriesByName = keyMap(
+ *   phoneBook,
+ *   entry => entry.name
+ * )
+ *
+ * // {
+ * //   Jon: { name: 'Jon', num: '555-1234' },
+ * //   Jenny: { name: 'Jenny', num: '867-5309' }
+ * // }
+ *
+ * const jennyEntry = entriesByName['Jenny']
+ *
+ * // { name: 'Jenny', num: '857-6309' }
+ * ```
+ */
+export function keyMap(list, keyFn) {
+  const result = Object.create(null);
+
+  for (const item of list) {
+    result[keyFn(item)] = item;
+  }
+
+  return result;
+}