chore!: simplified building process as no bundling is needed

Instead of using a bundler this library can rather just use the
Typescript Compiler. It does not bundle anything and just needs to be
transpiled.

This is slightly breaking as we only emit the mjs files, this should
work with all apps, but better safe than sorry.

Signed-off-by: Ferdinand Thiessen <opensource@fthiessen.de>

Author: susnux

lib/index.ts

@@ -10,7 +10,7 @@
  * @throws if the key can't be found
  */
 export function loadState<T>(app: string, key: string, fallback?: T): T {
-	const elem = <HTMLInputElement>document.querySelector(`#initial-state-${app}-${key}`)
+	const elem = document.querySelector<HTMLInputElement>(`#initial-state-${app}-${key}`)
 	if (elem === null) {
 		if (fallback !== undefined) {
 			return fallback