add permit2 as submodule, organize files to folders

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "lib/openzeppelin-contracts"]
 	path = lib/openzeppelin-contracts
 	url = https://github.com/OpenZeppelin/openzeppelin-contracts
+[submodule "lib/permit2"]
+	path = lib/permit2
+	url = https://github.com/Uniswap/permit2

src/Orders.sol

@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
+import {UsesPermit2, Permit2Batch} from "./permit2/UsesPermit2.sol";
+import {IOrders} from "./interfaces/IOrders.sol";
 import {IERC20} from "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
-import {Permit2Batch, UsesPermit2} from "./UsesPermit2.sol";
-import {IOrders} from "./IOrders.sol";
 
 /// @notice Contract capable of processing fulfillment of intent-based Orders.
 abstract contract OrderDestination is IOrders, UsesPermit2 {

src/Passage.sol

@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
+import {UsesPermit2, Permit2} from "./permit2/UsesPermit2.sol";
 import {IERC20} from "openzeppelin-contracts/contracts/token/ERC20/IERC20.sol";
 import {ERC20Burnable} from "openzeppelin-contracts/contracts/token/ERC20/extensions/ERC20Burnable.sol";
-import {UsesPermit2, Permit2} from "./UsesPermit2.sol";
 
 /// @notice A contract deployed to Host chain that allows tokens to enter the rollup.
 contract Passage is UsesPermit2 {

src/Zenith.sol

@@ -1,8 +1,6 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
-import {Passage} from "./Passage.sol";
-
 contract Zenith {
     /// @notice The address that is allowed to set/remove sequencers.
     address public immutable sequencerAdmin;

src/UsesPermit2.sol → src/permit2/UsesPermit2.sol

@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: UNLICENSED
 pragma solidity ^0.8.24;
 
-import {ISignatureTransfer} from "./vendored/ISignatureTransfer.sol";
-import {IOrders} from "./IOrders.sol";
+import {ISignatureTransfer} from "permit2/src/interfaces/ISignatureTransfer.sol";
+import {IOrders} from "../interfaces/IOrders.sol";
 
 /// @param permit - the permit2 batch token transfer details. includes a `deadline` and an unordered `nonce`.
 /// @param signer - the signer of the permit2 info; the owner of the tokens.

test/Orders.t.sol

@@ -4,9 +4,8 @@ pragma solidity ^0.8.24;
 import {Test, console2} from "forge-std/Test.sol";
 import {TestERC20} from "./Helpers.t.sol";
 import {ERC20} from "openzeppelin-contracts/contracts/token/ERC20/ERC20.sol";
-
 import {RollupOrders, OrderOrigin} from "../src/Orders.sol";
-import {IOrders} from "../src/IOrders.sol";
+import {IOrders} from "../src/interfaces/IOrders.sol";
 
 contract OrdersTest is Test {
     RollupOrders public target;