Infer simulation payload

[danbillson]

Updates the Simulation type to be generic allowing us to narrow down the type of the payload based on the event type, this will give intellisense on the payload when creating or updating simulations

or if you know the event type for the simulation you are retrieving, you can manually type it

const sim = await paddle.simulations.get<'subscription.created'>("ntfsim_01j990fgdbjyfqw28f19kvcgf2");

to get the typing on the payload.

Lists are maybe a little harder to try and narrow down so these are left alone but could be coerced by the user with something like

import type { SubscriptionNotification } from '@paddle/paddle-node-sdk'

const collection = paddle.simulations.list();
const list = await collection.next();
const payload = list[0].payload as SubscriptionNotification;