Agent Skills: fa-unit-economics-model

Provides the single shared, versioned unit-economics model for consumer one-off / in-app-purchase products, created in Discovery and re-run at every gate. Covers inputs (CPI, install->payer conversion, ARPPU, repeat purchase, ad ARPDAU), the gross-to-net stack (store commission, refunds, chargebacks, fraud, tax), LTV by segment, payback window, and a cashflow/working-capital check. Use whenever product economics must be initialized, updated with measured data, or evaluated at a gate.