feat(login): add auto-login splash UI and simplify app startup

src/App.tsx

@@ -1,33 +1,21 @@
-import { useCallback, useEffect, useState } from 'react';
+import { useEffect } from 'react';
 import { HashRouter, Route, Routes } from 'react-router-dom';
 import { LoginPage } from '@/pages/LoginPage';
 import { NotificationContainer } from '@/components/common/NotificationContainer';
 import { ConfirmationModal } from '@/components/common/ConfirmationModal';
-import { SplashScreen } from '@/components/common/SplashScreen';
 import { MainLayout } from '@/components/layout/MainLayout';
 import { ProtectedRoute } from '@/router/ProtectedRoute';
-import { useAuthStore, useLanguageStore, useThemeStore } from '@/stores';
-
-const SPLASH_DURATION = 1500;
-const SPLASH_FADE_DURATION = 400;
+import { useLanguageStore, useThemeStore } from '@/stores';
 
 function App() {
   const initializeTheme = useThemeStore((state) => state.initializeTheme);
   const language = useLanguageStore((state) => state.language);
   const setLanguage = useLanguageStore((state) => state.setLanguage);
-  const restoreSession = useAuthStore((state) => state.restoreSession);
-
-  const [splashReadyToFade, setSplashReadyToFade] = useState(false);
-  const [showSplash, setShowSplash] = useState(true);
-  const [authReady, setAuthReady] = useState(false);
 
   useEffect(() => {
     const cleanupTheme = initializeTheme();
-    void restoreSession().finally(() => {
-      setAuthReady(true);
-    });
     return cleanupTheme;
-  }, [initializeTheme, restoreSession]);
+  }, [initializeTheme]);
 
   useEffect(() => {
     setLanguage(language);
@@ -38,27 +26,6 @@ function App() {
     document.documentElement.lang = language;
   }, [language]);
 
-  useEffect(() => {
-    const timer = setTimeout(() => {
-      setSplashReadyToFade(true);
-    }, SPLASH_DURATION - SPLASH_FADE_DURATION);
-
-    return () => clearTimeout(timer);
-  }, []);
-
-  const handleSplashFinish = useCallback(() => {
-    setShowSplash(false);
-  }, []);
-
-  if (showSplash) {
-    return (
-      <SplashScreen
-        fadeOut={splashReadyToFade && authReady}
-        onFinish={handleSplashFinish}
-      />
-    );
-  }
-
   return (
     <HashRouter>
       <NotificationContainer />