implemented dynamic theme loading, working on user edit

frontend/src/App.svelte

@@ -9,12 +9,22 @@
     import User     from "./routes/user/User.svelte";
 
 
-    let translations_ready = false;
+    let translations_ready = $state(false);
     onMount(async () => {
         await loadTranslation('de','Login');
         translations_ready = true;
     });
 
+    function loadTheme(name){
+        if (!name) return;
+        console.log({theme:name});
+        const url = `${location.protocol}//${location.host.replace('5173','8080')}/css/${name}.css`;
+        fetch(url).then(resp => resp.text()).then(css => {
+            document.getElementById('usercss').innerText = css;
+        });
+    }
+
+    $effect(() => loadTheme(user.theme));
 </script>
 
 {#if translations_ready }