feat(tokens/hackathon): Squads-multisig hackathon prize program

[mikemaccana]

What this adds

An Anchor 1.0 example at tokens/hackathon/anchor: a hackathon prize program whose authority is an external Squads multisig vault PDA. The program is multisig-agnostic — it stores one authority pubkey and checks signer == hackathon.authority on committee-only handlers, leaving the propose/vote/execute flow to Squads.

Design

• One hackathon, many prizes. Each prize has its own PDA and its own vault ATA (owned by the prize PDA) that holds the prize in escrow.
• Committee vs. permissionless. create_hackathon, add_prize, set_winner, cancel_prize, and close_hackathon require the committee's signature. pay_winner is permissionless, so once the committee has recorded a winner, anyone can deliver the payout without the committee staying online.
• Token interface throughout (anchor_spl::token_interface), so the same compiled program works for both the Classic Token Program and the Token Extensions Program. One mint per prize lets a hackathon mix denominations (e.g. USDC for cash, a tokenized stock for a themed track).
• Safety: add_prize rejects zero amounts; pay_winner transfers exactly prize.amount via transfer_checked and marks the prize paid before the CPI; prize tokens live in program-owned vault PDAs with no admin escape outside the documented handlers.
• The hackathon name is hashed into its PDA seed via the sol_sha256 syscall (solana-sha256-hasher), with an sha2 fallback for host/IDL builds.

Handlers

Handler	Signer	Accounts created / changed
create_hackathon	Committee	Creates Hackathon.
add_prize	Committee	Creates Prize + vault ATA; increments prize_count.
set_winner	Committee	Sets Prize.winner.
pay_winner	Anyone	Moves tokens vault → winner; sets Prize.paid.
cancel_prize	Committee	Refunds vault; closes it; sets Prize.cancelled.
close_hackathon	Committee	Closes Hackathon once every prize is resolved.

Tests

Rust + LiteSVM integration tests build a real Squads v4 2-of-3 multisig and drive the full propose/vote/execute flow — happy path, failure cases (zero amount, no winner, under-funded, already paid, non-committee signer), and lifecycle (cancel and close). Run with:

cd tokens/hackathon/anchor
cargo build-sbf
cargo test

Docs

The README covers the concepts for newcomers (with links to definitions on first use), a worked walkthrough with named committee members and sample tokens (USDC, NVDAx, TSLAx), the account layout, and the handler-to-account mapping.

https://claude.ai/code/session_01DBFPwFobdi4SKkDq4BZdd8