feat: integrate sonner for toast notifications across multiple pages

src/pages/RegisterPage.tsx

@@ -4,6 +4,7 @@ import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
 import { Label } from '@/components/ui/label'
 import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card'
+import { toast } from 'sonner'
 import { useAuth } from '@/hooks/use-auth'
 import { authService } from '@/services/auth'
 
@@ -72,9 +73,12 @@ export function RegisterPage() {
 
     try {
       await register(formData.email, formData.password, formData.name)
+      toast.success('Account created successfully! Welcome!')
       navigate('/')
     } catch (error) {
-      setError(error instanceof Error ? error.message : 'Registration failed')
+      const errorMessage = error instanceof Error ? error.message : 'Registration failed'
+      setError(errorMessage)
+      toast.error(errorMessage)
     } finally {
       setLoading(false)
     }