docs: document how rewards are delivered to winners

## Problem

The site presents the **Rewards** section with concrete amounts (`$2048` / `$1024` / `$512`) and the list of awarded projects, but it does not document **how a reward is actually delivered to a winner**. The evaluation pipeline is described in good detail (automated filtering, two-reviewer scoring, steering committee decision), yet the final step — the payout — is left implicit.

## What is missing

| Topic | Currently undocumented |
|---|---|
| Winner obligations | What the winner must provide (e.g. a wallet address) and where to submit it |
| Notification | How and when winners are contacted after the announcement |
| Timeline | Expected timeframe between the announcement and the payout |

## Suggested fix

Add a short **"How the reward is paid"** subsection (or an FAQ entry) next to the Rewards block, covering the currency options, the fact that a winner is contacted and shares a payout address, and the expected timeframe. A few sentences would remove the ambiguity and make the reward policy as transparent as the judging process already is.

Start at the site's Rewards section, where the amounts and awarded projects are presented, and read the surrounding evaluation-policy content. Add a short "How the reward is paid" subsection or FAQ covering currency options, winner notification and payout-address submission, and the expected payout timeframe; the documentation is done when the delivery process is no longer implicit.

Written by the indexing model from the issue text.