code and layout refactoring

frontend/src/components/Footer.tsx

@@ -0,0 +1,56 @@
+import SettingsEthernet from '@mui/icons-material/SettingsEthernet'
+import { AppBar, Toolbar } from '@mui/material'
+import { Suspense } from 'react'
+import { useRecoilValue } from 'recoil'
+import { settingsState } from '../atoms/settings'
+import { connectedState } from '../atoms/status'
+import { useI18n } from '../hooks/useI18n'
+import FreeSpaceIndicator from './FreeSpaceIndicator'
+import GitHubIcon from '@mui/icons-material/GitHub'
+
+const Footer: React.FC = () => {
+  const settings = useRecoilValue(settingsState)
+  const isConnected = useRecoilValue(connectedState)
+
+  const mode = settings.theme
+  const { i18n } = useI18n()
+
+  return (
+    <AppBar position="fixed" color="default" sx={{
+      top: 'auto',
+      bottom: 0,
+      height: 48,
+      zIndex: 1200,
+      borderTop: mode === 'light'
+        ? '1px solid rgba(0, 0, 0, 0.12)'
+        : '1px solid rgba(255, 255, 255, 0.12)',
+    }}>
+      <Toolbar sx={{
+        paddingBottom: 2,
+        fontSize: 14,
+        display: 'flex', gap: 1, justifyContent: 'space-between'
+      }}>
+        <div>v3.0.6</div>
+        <div style={{ display: 'flex', gap: 1 }}>
+          <div style={{
+            display: 'flex',
+            alignItems: 'center',
+            flexWrap: 'wrap',
+            marginRight: '8px',
+            gap: 3,
+          }}>
+            <SettingsEthernet />
+            <span>
+              {isConnected ? settings.serverAddr : i18n.t('notConnectedText')}
+            </span>
+          </div>
+          <Suspense fallback={i18n.t('loadingLabel')}>
+            <FreeSpaceIndicator />
+          </Suspense>
+        </div>
+      </Toolbar>
+    </AppBar>
+  )
+}
+
+export default Footer