Builds a one-off tracked link for an offer (offer_uuid). The returned link is the offer's tracking URL with tracking parameters appended as merge tags that resolve at send time (email address, mailing identifier, contact identifier, affiliate identifier), controlled by the include_ flags. Because those tags only resolve when the link is sent through a message, turn the include_ flags off for a link used outside a send. An offer link inside a broadcast body is not built here: link the offer to the broadcast with offer_uuids on create_broadcast or with set_broadcast_offers, and paste the variable returned for that offer into the body. A link pasted into a broadcast body instead of the variable carries no attribution token, so conversions cannot be tied back to the contact. Requires a connected offer integration. Both GET and POST are accepted.