switch link checking library, fixes #2, initial config window

js/preload.js

@@ -0,0 +1,10 @@
+window.addEventListener('DOMContentLoaded', () => {
+    const replaceText = (selector, text) => {
+        const element = document.getElementById(selector)
+        if (element) element.innerText = text
+    }
+
+    for (const type of ['chrome', 'node', 'electron']) {
+        replaceText(`${type}-version`, process.versions[type])
+    }
+})