Capacity growth projection, per financial product with growth support.

Explains how the borrower's max borrowing capacity on a financial product grows over
usage "cycles": real past growth steps when the borrower is already in a cycle, and
1-2 illustrative future steps assuming on-time repayment. Amounts are always computed
server-side; internal configuration and income figures are never returned, only the
resulting curve (and whether it has plateaued, via is_near_cap). A projected step can
also carry is_less_certain: even a step the curve keeps climbing toward can
need a human at deployment time, independently of is_near_cap. is_less_precise
flags the whole projection when it couldn't be based on the borrower's own income
figure and fell back to a generic cap instead.

Returns one entry per eligible financial product. Only the receivable financing
product has cycle support today, so the list currently has at most one entry — an
empty list means the borrower has no such product yet.