chore: drop node 14, 16 support since vitest doesn't support it

Author: nathanhleung

.github/workflows/test.yml

@@ -11,7 +11,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [14.13.x, 16.x, 18.x, 20.x, 22.x]
+        node-version: [18.x, 20.x, 22.x, 24.x]
 
     steps:
       - name: Checkout

package.json

@@ -31,7 +31,7 @@
   "author": "nathanhleung@gmail.com",
   "license": "CC0-1.0",
   "engines": {
-    "node": "^14.13.1 || >=16.0.0"
+    "node": ">=18.0.0"
   },
   "devDependencies": {
     "prettier": "^3.6.2",

src/index.test.ts

@@ -1,6 +1,5 @@
 import { describe, test, expect, vi } from "vitest";
 import { generateKeyBetween, generateNKeysBetween } from "./index";
-import { generateNKeysBetween as unjitteredGenerateNKeysBetween } from "fractional-indexing";
 
 describe("validateJitterBits", () => {
   test("should throw error for non-integer jitterBits", () => {