feat(usermanagement): enhance user-branch relationship by syncing branches and adding timestamps

app/Http/Controllers/UsersController.php

@@ -217,11 +217,23 @@ class UsersController extends Controller
 
         if ($validated) {
             $user = User::create($validated);
+
             if ($user) {
                 if ($request->roles) {
                     $user->assignRole($request->roles);
                 }
 
+                $branches = $request->input('branches', []);
+
+                $user->branches()->sync($branches);
+
+                if (!empty($branches)) {
+                    $firstBranchId = $branches[0];
+
+                    $user->branch_id = $firstBranchId;
+                    $user->save();
+                }
+
                 return redirect()->route('users.index')->with('success', 'User created successfully.');
             }
         }