Add paid_amount , balance_amount, tax_exclusive_amount available to apiv4

[eileenmcnaughton]

Overview

Add paid_amount , balance_amount, tax_exclusive_amount available to apiv4

This makes these three fields available as tokens and as fields for apiv4

Re-instatement of #23802 (plus one more field)

Before

now you don't see it

After

now you do

Technical Details

This PR was open before but with two issues

• there was an initial question about performance. This was resolved in discussion on wip - add paid_amount & balance_amount to apiv4 #23802 in that @colemanw clarified that these pseudo fields are not fetched unless specifically requested
• the second issue was that wip - add paid_amount & balance_amount to apiv4 #23802 had cleanup in the invoice template that went way beyond just these fields. I opted to do that cleanup first & closed the PR until that was merged so this PR could narrowly target the fields I am focussed on

Comments

[civibot]

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