feat: reorganize admin settings with tabbed interface and documentation

- Reorganized admin settings into tabbed interface (General, Security, Payment Methods)
- Vertical tabs on desktop, horizontal scrollable on mobile
- Moved Payment Methods from separate menu to Settings tab
- Fixed admin profile reuse and dashboard blocking
- Fixed maintenance mode guard to use AppConfig model
- Added admin auto-redirect after login (admins → /admin, users → /)
- Reorganized documentation into docs/ folder structure
- Created comprehensive README and documentation index
- Added PWA and Web Push notifications to to-do list

apps/web/src/components/pages/OtpVerification.tsx

@@ -57,9 +57,13 @@ export function OtpVerification() {
     setLoading(true)
 
     try {
-      await verifyOtp(tempToken, code, method)
-      // Verification successful, redirect to dashboard
-      navigate('/')
+      const result = await verifyOtp(tempToken, code, method)
+      // Verification successful, redirect based on role
+      if (result.user?.role === 'admin') {
+        navigate('/admin')
+      } else {
+        navigate('/')
+      }
     } catch (err) {
       const error = err as { response?: { data?: { message?: string } } }
       setError(error.response?.data?.message || 'Invalid OTP code. Please try again.')