fix: address CodeRabbit review nitpicks

- Add checkStatus to useEffect dependency array (avoid stale closure)
- Redirect unknown dashboard paths to /dashboard instead of showing home

Author: DevanshuNEU

frontend/src/components/Dashboard.tsx

@@ -1,4 +1,4 @@
-import { Routes, Route } from 'react-router-dom'
+import { Routes, Route, Navigate } from 'react-router-dom'
 import { DashboardLayout } from './dashboard/DashboardLayout'
 import { DashboardHome } from './dashboard/DashboardHome'
 import { SettingsPage } from '../pages/SettingsPage'
@@ -9,7 +9,7 @@ export function Dashboard() {
       <Routes>
         <Route index element={<DashboardHome />} />
         <Route path="settings" element={<SettingsPage />} />
-        <Route path="*" element={<DashboardHome />} />
+        <Route path="*" element={<Navigate to="/dashboard" replace />} />
       </Routes>
     </DashboardLayout>
   )

frontend/src/pages/SettingsPage.tsx

@@ -43,7 +43,7 @@ export function SettingsPage() {
   useEffect(() => {
     checkStatus()
     fetchRepos()
-  }, [])
+  }, [checkStatus])
 
   const fetchRepos = async () => {
     if (!session?.access_token) return