This PR introduces 3 main features:

• Calculates the maximum allowed quantity for a refund based on previously refunded items
• Allows to change the final product refund amount, by tapping on the sum (it has been decided that we should postpone introducing this functionality for now, so I only enabled it for this PR to test the functionality)
• Extracts the product list from the common view state object due to performance reasons (just like it was done in product list & review list)
• Select all button becomes Select none when all items are selected

Note: The refund flow is not working in this PR yet. It's completed in #1635.

To test:

Max quantity limit

1. Create an order with multiple items
2. Go to the order detail, issue a refund and verify the item number picker shows the correct value
3. On the web, refund some items while leaving some in the order
4. Refresh the order in the app, issue a refund and verify the number picker only shows the leftover number of items choose from, based on the previous refund
5. Close the dialog and tap the Select all button
6. Notice the refund quantity for each item is limited based on the previous refunds

Custom products refund amount

1. Open an order and issue a refund
2. Select a couple of items for refund and notice the total amount
3. Tap on the amount and notice a currency dialog appears
4. Change the amount and confirm
5. Notice the refund total changed
6. Tap Next and notice the custom amount is shown in the summary
7. Go back to the previous screen
8. Tap on the Select all button
9. Notice the total refund amount is automatically recalculated again

Select all button

1. Open an order and issue a refund
2. Tap the Select all button
3. Notice the button title changes to Select none and all items are selected
4. Tap the Select none button
5. Notice the button title changes to Select all and no items are selected

Note: #1629 should be merged before this PR.