Adding interface v2 wrapper to AT, DE and FR

[LeilaZarban]

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[volllly]

Something that we could also add to this package are extension methods for the ReceiptRequest and ReceiptResponse and ChargeItems and PayItems to get the value of all of these Flags 😅

At the moment we have multiple implementations of these extensions for the relevant flags in multiple of the projects in this repo and in the exports etc.
To reduce the duplication we could define them in this new package and reuse them everywhere.

• Implement using source generators