Add Telegram Mini App login flow

app/middleware/auth.global.ts

@@ -4,11 +4,22 @@ export default defineNuxtRouteMiddleware((to) => {
   const authToken = useCookie<string | null>(authCookieName);
 
   const isLoginPage = to.path === '/login';
+  const loginToken = typeof to.query.login_token === 'string' ? to.query.login_token.trim() : '';
+  const nextPath = to.fullPath.startsWith('/') ? to.fullPath : '/';
+
   if (!authToken.value && !isLoginPage) {
-    return navigateTo('/login');
+    return navigateTo({
+      path: '/login',
+      query: {
+        next: nextPath,
+      },
+    });
   }
 
-  if (authToken.value && isLoginPage) {
-    return navigateTo('/');
+  if (authToken.value && isLoginPage && !loginToken) {
+    const requestedNextPath = typeof to.query.next === 'string' && to.query.next.startsWith('/')
+      ? to.query.next
+      : '/';
+    return navigateTo(requestedNextPath);
   }
 });