🎛️ refactor: HeaderBar into modular components, add shared skeletons, and primary-colored nav hover

Summary
- Split HeaderBar into maintainable components and hooks
- Centralized skeleton loading UI via a reusable SkeletonWrapper
- Improved navigation UX with primary-colored hover indication
- Preserved API surface and passed linters

Why
- Improve readability, reusability, and testability of the header
- Remove duplicated skeleton logic across files
- Provide clearer hover feedback consistent with the theme

What’s changed
- Components (web/src/components/layout/HeaderBar/)
  - New container: index.js
  - New UI components: HeaderLogo.js, Navigation.js, ActionButtons.js, UserArea.js, MobileMenuButton.js, NewYearButton.js, NotificationButton.js, ThemeToggle.js, LanguageSelector.js
  - New shared skeleton: SkeletonWrapper.js
  - Updated entry: HeaderBar.js now re-exports ./HeaderBar/index.js
- Hooks (web/src/hooks/common/)
  - New: useHeaderBar.js (state and actions for header)
  - New: useNotifications.js (announcements state, unread calc, open/close)
  - New: useNavigation.js (main nav link config)
- Skeleton refactor
  - Navigation.js: replaced inline skeletons with <SkeletonWrapper type="navigation" .../>
  - UserArea.js: replaced inline skeletons with <SkeletonWrapper type="userArea" .../>
  - HeaderLogo.js: replaced image/title skeletons with <SkeletonWrapper type="image"/>, <SkeletonWrapper type="title"/>
- Navigation hover UX
  - Added primary-colored hover to nav items for clearer pointer feedback
  - Final hover style: hover:text-semi-color-primary (kept rounded + transition classes)

Non-functional
- No breaking API changes; HeaderBar usage stays the same
- All modified files pass lint checks

Notes for future work
- SkeletonWrapper is extensible: add new cases (e.g., card) in one place
- Components are small and test-friendly; unit tests can be added per component

Affected files (key)
- web/src/components/layout/HeaderBar.js
- web/src/components/layout/HeaderBar/index.js
- web/src/components/layout/HeaderBar/Navigation.js
- web/src/components/layout/HeaderBar/UserArea.js
- web/src/components/layout/HeaderBar/HeaderLogo.js
- web/src/components/layout/HeaderBar/ActionButtons.js
- web/src/components/layout/HeaderBar/MobileMenuButton.js
- web/src/components/layout/HeaderBar/NewYearButton.js
- web/src/components/layout/HeaderBar/NotificationButton.js
- web/src/components/layout/HeaderBar/ThemeToggle.js
- web/src/components/layout/HeaderBar/LanguageSelector.js
- web/src/components/layout/HeaderBar/SkeletonWrapper.js
- web/src/hooks/common/useHeaderBar.js
- web/src/hooks/common/useNotifications.js
- web/src/hooks/common/useNavigation.js

web/src/components/layout/HeaderBar/HeaderLogo.js

@@ -0,0 +1,81 @@
+/*
+Copyright (C) 2025 QuantumNous
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as
+published by the Free Software Foundation, either version 3 of the
+License, or (at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+For commercial licensing, please contact support@quantumnous.com
+*/
+
+import React from 'react';
+import { Link } from 'react-router-dom';
+import { Typography, Tag } from '@douyinfe/semi-ui';
+import SkeletonWrapper from './SkeletonWrapper.js';
+
+const HeaderLogo = ({
+  isMobile,
+  isConsoleRoute,
+  logo,
+  logoLoaded,
+  isLoading,
+  systemName,
+  isSelfUseMode,
+  isDemoSiteMode,
+  t,
+}) => {
+  if (isMobile && isConsoleRoute) {
+    return null;
+  }
+
+  return (
+    <Link to="/" className="flex items-center gap-2">
+      <div className="relative w-8 h-8 md:w-8 md:h-8">
+        <SkeletonWrapper
+          loading={isLoading || !logoLoaded}
+          type="image"
+        />
+        <img
+          src={logo}
+          alt="logo"
+          className={`absolute inset-0 w-full h-full transition-opacity duration-200 group-hover:scale-105 rounded-full ${(!isLoading && logoLoaded) ? 'opacity-100' : 'opacity-0'}`}
+        />
+      </div>
+      <div className="hidden md:flex items-center gap-2">
+        <div className="flex items-center gap-2">
+          <SkeletonWrapper
+            loading={isLoading}
+            type="title"
+            width={120}
+            height={24}
+          >
+            <Typography.Title heading={4} className="!text-lg !font-semibold !mb-0">
+              {systemName}
+            </Typography.Title>
+          </SkeletonWrapper>
+          {(isSelfUseMode || isDemoSiteMode) && !isLoading && (
+            <Tag
+              color={isSelfUseMode ? 'purple' : 'blue'}
+              className="text-xs px-1.5 py-0.5 rounded whitespace-nowrap shadow-sm"
+              size="small"
+              shape='circle'
+            >
+              {isSelfUseMode ? t('自用模式') : t('演示站点')}
+            </Tag>
+          )}
+        </div>
+      </div>
+    </Link>
+  );
+};
+
+export default HeaderLogo;