Merge a17t-redesign, kinda ts-ify setup.js

the web ui has been redesigned with the a17t toolkit, which imo looks a
lot better than bootstrap. This also brought a complete rework of the
web code, which now makes a lot more sense hopefully. the setup page is
still stuck with bootstrap, its not much of a priority but i'll rewrite
it eventually.

ts/modules/theme.ts

@@ -0,0 +1,16 @@
+export function toggleTheme() {
+    document.documentElement.classList.toggle('dark-theme');
+    document.documentElement.classList.toggle('light-theme');
+    localStorage.setItem('theme', document.documentElement.classList.contains('dark-theme') ? "dark" : "light");
+}
+
+export function loadTheme() {
+    const theme = localStorage.getItem("theme");
+    if (theme == "dark") {
+        document.documentElement.classList.add('dark-theme');
+        document.documentElement.classList.remove('light-theme');
+    } else if (theme == "light") {
+        document.documentElement.classList.add('light-theme');
+        document.documentElement.classList.remove('dark-theme');
+    }
+}