fix: add /mobile prefix to all client-side fetch() calls for basePath

src/app/forum/page.tsx

@@ -87,7 +87,7 @@ export default function ForumPage() {
 
   const fetchCategories = useCallback(async () => {
     try {
-      const res = await fetch("/api/forum/categories");
+      const res = await fetch("/mobile/api/forum/categories");
       const data = await res.json();
       if (res.ok) {
         setCategories(data.categories);
@@ -159,7 +159,7 @@ export default function ForumPage() {
     setCreating(true);
 
     try {
-      const res = await fetch("/api/forum/threads", {
+      const res = await fetch("/mobile/api/forum/threads", {
         method: "POST",
         headers: {
           "Content-Type": "application/json",