USER STORY: Delete existing booking

[KatePaulauskas]

As a Registered Customer I can delete my existing booking so that I can remove an appointment I no longer need.

Acceptance Criteria:

• Given existing customer is viewing their upcoming appointments on "My Bookings" page
• Then the customer should have a "Delete" option for each appointment
• Given the customer selects to click the "Delete" button to delete an appointment
• Then the customer should be prompted to confirm the deletion to prevent accidental removal
• Given the customer have confirmed the deletion
• Then the appointment should be deleted, and the customer should see a confirmation message

Tasks:

• [x] Add a delete button and confirmation modal to the bookings page.
• [x] Update the view to handle the delete operation securely.

[KatePaulauskas]

Logged-in users are able to delete their appointments after confirming their selected action.