Update" Button Text Disappears When Changing Vehicle Type – Loader Should Appear Instead

Describe the bug
When the user changes the Vehicle Type in the app, the text on the "Update" button disappears during the update process. This may confuse users, as there is no indication that the update is in progress.

To Reproduce
Steps to reproduce the behavior:

Open the app and navigate to the Vehicle Type section.
Select a different vehicle type.
Tap the "Update" button.
Observe that the button text disappears instead of showing a loader.
Expected behavior
A loading indicator (spinner or progress animation) should appear on the "Update" button to provide visual feedback that the update is in progress.

Smartphone (please complete the following information):

Device: Samsung A15

Additional context
Replacing the disappearing text with a loader improves user experience by confirming that their action is being processed, preventing repeated taps or confusion.

No file or test is named. Start by locating the Vehicle Type screen and the Update button handler, then reproduce the behavior on a Samsung A15 or equivalent device. Done means the button shows a loading indicator while the vehicle type update is in progress and no longer loses its feedback during the request.