feat: Add L2CM implementation

.semgrep/rules/sol-rules.yaml

@@ -330,6 +330,7 @@ rules:
         - packages/contracts-bedrock/src/L2/FeeVault.sol
         - packages/contracts-bedrock/src/L2/OptimismMintableERC721.sol
         - packages/contracts-bedrock/src/L2/OptimismMintableERC721Factory.sol
+        - packages/contracts-bedrock/src/L2/L2ContractsManager.sol
         - packages/contracts-bedrock/src/cannon/MIPS64.sol
         - packages/contracts-bedrock/src/cannon/PreimageOracle.sol
         - packages/contracts-bedrock/src/dispute/AnchorStateRegistry.sol

packages/contracts-bedrock/interfaces/L2/IL2ContractsManager.sol

@@ -1,10 +1,41 @@
 // SPDX-License-Identifier: MIT
 pragma solidity ^0.8.0;
 
+// Interfaces
+import { ISemver } from "interfaces/universal/ISemver.sol";
+
+// Libraries
+import { L2ContractsManagerTypes } from "src/libraries/L2ContractsManagerTypes.sol";
+
 /// @title IL2ContractsManager
 /// @notice Interface for the L2ContractsManager contract.
-interface IL2ContractsManager {
+interface IL2ContractsManager is ISemver {
+    /// @notice Thrown when the upgrade function is called outside of a DELEGATECALL context.
+    error L2ContractsManager_OnlyDelegatecall();
+
+    /// @notice Thrown when a user attempts to downgrade a contract.
+    /// @param _target The address of the contract that was attempted to be downgraded.
+    error L2ContractsManager_DowngradeNotAllowed(address _target);
+
+    /// @notice Error thrown when a semver string has less than 3 parts.
+    error SemverComp_InvalidSemverParts();
+
+    /// @notice Thrown when a contract is in the process of being initialized during an upgrade.
+    error L2ContractsManager_InitializingDuringUpgrade();
+
     /// @notice Executes the upgrade for all predeploys.
     /// @dev This function MUST be called via DELEGATECALL from the L2ProxyAdmin.
     function upgrade() external;
+
+    /// @notice Returns the implementation addresses for each predeploy upgraded by the L2ContractsManager.
+    /// @return implementations_ The implementation addresses for each predeploy upgraded by the L2ContractsManager.
+    function getImplementations()
+        external
+        view
+        returns (L2ContractsManagerTypes.Implementations memory implementations_);
+
+    /// @notice Constructor for the L2ContractsManager contract.
+    /// @param _implementations The implementation struct containing the new implementation addresses for the L2
+    /// predeploys.
+    function __constructor__(L2ContractsManagerTypes.Implementations memory _implementations) external;
 }