Refactor login flow to return redirect URL instead of direct navigation

Move navigation responsibility from useAuth composable to login page
component for better separation of concerns and component control.

composables/useAuth.ts

@@ -79,16 +79,19 @@ export const useAuth = () => {
         if (sessionSuccess) {
           console.log('👤 User data retrieved from session:', user.value);
           
-          // Redirect to dashboard or intended page
-          console.log('🔄 Redirecting to:', response.redirectTo || '/dashboard');
-          await navigateTo(response.redirectTo || '/dashboard');
-          
-          return { success: true };
+          // Return redirect URL for the component to handle
+          console.log('✅ Login successful, returning redirect URL:', response.redirectTo || '/dashboard');
+          return { 
+            success: true, 
+            redirectTo: response.redirectTo || '/dashboard' 
+          };
         } else {
           console.warn('❌ Failed to get user data from session after login');
-          // Still redirect since login was successful on server
-          await navigateTo('/dashboard');
-          return { success: true };
+          // Still return success with redirect since login was successful on server
+          return { 
+            success: true, 
+            redirectTo: '/dashboard' 
+          };
         }
       }