Add eventlistener for change of day/night mode

And add a static js folder for js-files apart from the asset pipeline.

assets/js/app.js

@@ -22,7 +22,8 @@ import {Socket} from "phoenix"
 import {LiveSocket} from "phoenix_live_view"
 import topbar from "../vendor/topbar"
 
-import {DarkModeHook} from './dark-mode'
+import {DarkModeHook} from './dark-mode-widget'
+
 let csrfToken = document.querySelector("meta[name='csrf-token']").getAttribute("content")
 let liveSocket = new LiveSocket("/live", Socket, {
   params: {_csrf_token: csrfToken},
@@ -42,4 +43,3 @@ liveSocket.connect()
 // >> liveSocket.enableLatencySim(1000)  // enabled for duration of browser session
 // >> liveSocket.disableLatencySim()
 window.liveSocket = liveSocket
-