Add L2 deploy function and L2 audit reports

deploy/UsdsDeploy.sol

@@ -23,7 +23,7 @@ import { Usds } from "src/Usds.sol";
 import { UsdsJoin } from "src/UsdsJoin.sol";
 import { DaiUsds } from "src/DaiUsds.sol";
 
-import { UsdsInstance } from "./UsdsInstance.sol";
+import { UsdsInstance, UsdsL2Instance } from "./UsdsInstance.sol";
 
 interface DaiJoinLike {
     function vat() external view returns (address);
@@ -47,4 +47,16 @@ library UsdsDeploy {
         instance.usdsJoin = _usdsJoin;
         instance.daiUsds  = _daiUsds;
     }
+
+    function deployL2(
+        address deployer,
+        address owner
+    ) internal returns (UsdsL2Instance memory instance) {
+        address _usdsImp = address(new Usds());
+        address _usds = address((new ERC1967Proxy(_usdsImp, abi.encodeCall(Usds.initialize, ()))));
+        ScriptTools.switchOwner(_usds, deployer, owner);
+
+        instance.usds     = _usds;
+        instance.usdsImp  = _usdsImp;
+    }
 }

deploy/UsdsInstance.sol

@@ -22,3 +22,8 @@ struct UsdsInstance {
     address usdsJoin;
     address daiUsds;
 }
+
+struct UsdsL2Instance {
+    address usds;
+    address usdsImp;
+}

test/L2Deployment.t.sol

@@ -0,0 +1,43 @@
+// SPDX-FileCopyrightText: © 2024 Dai Foundation <www.daifoundation.org>
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+pragma solidity ^0.8.21;
+
+import "dss-test/DssTest.sol";
+
+import { Upgrades } from "openzeppelin-foundry-upgrades/Upgrades.sol";
+
+import { UsdsL2Instance } from "deploy/UsdsInstance.sol";
+import { UsdsDeploy } from "deploy/UsdsDeploy.sol";
+
+import { Usds } from "src/Usds.sol";
+
+contract L2DeploymentTest is DssTest {
+
+    address l2GovRelay = address(222);
+    UsdsL2Instance inst;
+
+    function setUp() public {
+        inst = UsdsDeploy.deployL2(address(this), l2GovRelay);
+    }
+
+    function testSetUp() public view {
+        assertEq(Usds(inst.usds).wards(l2GovRelay), 1);
+        assertEq(Usds(inst.usds).wards(address(this)), 0);
+        assertEq(Upgrades.getImplementationAddress(inst.usds), inst.usdsImp);
+        assertEq(Usds(inst.usds).version(), "1");
+    }
+}