Replace the old multi-file ingot structure (13 .fe files) with a single
bountiful.fe using the new effects-based contract model. The 6 game
variants and trait system are consolidated into one Game contract due to
compiler limitations (StorageMap structs can't be passed as values,
tuple ABI arity cap).

Key changes:
- Contracts use msg/recv blocks instead of pub fn with Context
- Storage uses StorageMap effects instead of inline Map fields
- Cross-contract calls use Call effect instead of stub contracts
- Board stored in StorageMap<u256,u256> instead of Array<u256,16>
- Reverts replaced with error code returns
- 8 Fe-native tests (fe test) replace the old Hardhat test suite

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

…er limitations

Split the single bountiful.fe into a proper Fe ingot structure:
- src/lib.fe: shared error codes, constants, helpers, cross-contract msg interfaces
- src/game.fe: Game contract (15-puzzle challenge)
- src/registry.fe: BountyRegistry contract (bounty platform)

The standalone bountiful.fe is kept for running tests (fe test only discovers
#[test] in the root module, and cross-module contract refs cause an ICE).

Add LIMITATIONS.md documenting 6 Fe compiler limitations for GitHub issues.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

GameBitboard (bitwise u256 board), Game2D (nested 2D arrays),
and GameEnum (enum/match/struct impl) — exercises distinct Fe
language features. All 14 tests pass.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Delete the 1093-line monolith and activate the child module files in
src/. Tests now live in lib.fe and import contracts from child modules
via `use ingot::*`. All 14 tests pass.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Port 7 new tests from the old JS test suite: non-admin register,
admin register+check, remove unlocked, remove while locked, claim
without lock, claim unregistered, claim unsolved.

Fix critical bug: all tests used args: (0,) as admin_inner, but
ctx.caller() in Fe test EVM is the test contract's address (not
Address::ZERO). Use evm.address().inner to correctly set admin.
This also fixes test_full_bounty_flow which was silently a no-op.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

The workaround test was needed because the Fe test runner only checked
lib.fe for #[test] functions. This has been fixed upstream, so the
workaround can be removed.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Restructure the flat single-ingot project into a workspace with
dedicated ingots for better separation of concerns:

  shared   — error codes, constants, cross-contract msg interfaces,
             game_util helpers, DummyLockValidator test utility
  registry — BountyRegistry contract, DummyGame test utility
  games    — Game, Game2D, GameBitboard, GameEnum contracts

Dependency graph (no cycles):
  shared ← registry
  shared ← games

DummyLockValidator lives in shared (not games) so both registry and
games tests can deploy it without creating a circular dependency.
DummyGame in registry replaces the real Game contract in registry tests,
eliminating the games→registry→games cycle.

All 26 tests pass (shared: 1, registry: 14, games: 11).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Migrate e2e testing from Hardhat to Foundry to cover scenarios Fe's
test runner cannot: block advancement (vm.roll), ETH value transfers,
and multi-account authorization (vm.prank). 21 tests across two suites.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Deploys BountyRegistry + Game, registers the game as a challenge, and
initializes a solvable 15-puzzle board. Configurable lock deposit via
LOCK_DEPOSIT env var (default 0.01 ETH).

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Introduce a shared Error enum with to_int() for type-safe,
sequential error codes (1-8) instead of scattered constants
with gaps. Update all contracts and Foundry test constants.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Drop hardhat.config.js, package.json, old JS test files, and Hardhat
deployment scripts. Update .gitignore for Foundry build artifacts.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

IGame pretended to be universal but didn't match all game variants
(game_2d has a different getBoard signature). The registry only needs
isSolved(), so that's the shared interface now. Tests and deploy script
define their own local IGame for variant-specific methods.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

These APIs answer yes/no questions and should return bool instead of
u256. Also changes open_challenges map to StorageMap<Address, bool>.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>