New transaction page - disable "Save" Button Until All Required Fields Are Completed

[Lalita-Lala]

Describe the task
When the user clicks on the “New Transaction” button on Credit Agreements page, they are redirected to the page for creating a new transaction. On this page, the "Save" button is immediately enabled, even before any required fields have been completed. This behavior is both confusing for the user and allows them to save an agreement without providing the necessary information in mandatory fields, such as Transaction Date, Transaction Type, and Vehicle Supplier.
This is incorrect, as incomplete data should not be saved because for example if the credit agreement does not have a date attached to it, the director gets an error when they try to issue credits. The "Save" button should only become enabled after all required fields are properly filled out.

Mockups and prototypes
Proto
Mockups

Purpose
To ensure that users cannot save transactions with incomplete or missing required information. This change aims to improve data accuracy, reduce confusion, and prevent errors when agreements are submitted with missing data.

Acceptance Criteria

• The "Save" button is disabled by default when the user enters the “New transaction” agreement page.
• The "Save" button becomes enabled only after the user completes all required fields, including Transaction Date, Transaction Type, and Vehicle Supplier.
• A tool-tip is displayed when hovering over the disabled "Save" button with the message: “Please fill in all the required fields to enable the “Save” button.”
• Incomplete agreements cannot be saved or submitted for next step.

[Lalita-Lala]

This ticket was created based on this 2301

[rogerlcleung]

Changes in PR #2406 also include disabling the "Submit to Director" button when there is any zero credit entry.