contracts: revive SuperchainTokenBridge + add SuperchainERC20Factory (wrap/unwrap)

[opsuperchain]

Description

This PR revives the SuperchainTokenBridge and adds a new SuperchainERC20Factory that lets any existing ERC20 be wrapped into a SuperchainERC20 and moved across the Superchain.

Commit 1: revive the SuperchainTokenBridge

SuperchainTokenBridge, SuperchainERC20, and IERC7802 were removed in #19999 (and #20141) as unused interop contracts. This commit restores them from history at their original semvers and predeploy slot (0x4200...0028), adapted to the predeploy machinery that has landed since (Predeploys.getAllRecords() registry, L2ContractsManager deploy/upgrade flow, gate assertions in L2Genesis). The bridge is gated behind interop exactly like SuperchainETHBridge/ETHLiquidity. The legacy OptimismSuperchainERC20 lane (beacon, factory, L2StandardBridgeInterop) is intentionally not revived; the new factory below replaces it.

Commit 2: SuperchainERC20Factory

A minimal wrap/unwrap factory, added as an interop-gated predeploy at 0x4200...0026 (the slot freed by the old OptimismSuperchainERC20Factory):

• deploy(chainId, token, name, symbol, decimals) deploys a SuperchainWrappedERC20 via CREATE2 with salt = keccak256(chainId, token). The wrapped token's constructor takes no arguments (metadata is read back from the factory during construction), so its initcode is constant and the wrapped token address is identical on every chain, derived purely from the [chain_id, address] identity of the original token.
• On the original token's chain, metadata is read from the token itself (falling back to caller-supplied values for tokens without the metadata extension). On remote chains the deployer supplies it — or, better, uses propagation:
• propagate(token, toChainId) sends the canonical wrapped metadata from the token's home chain to the factory on another chain via the L2ToL2CrossDomainMessenger (the factory is the same predeploy address everywhere, mirroring SuperchainTokenBridge.sendERC20/relayERC20). relayDeploy on the destination requires the messenger, the factory itself as cross-domain sender, and message source chain == the token's claimed home chain, so remote chains get authentic metadata without trusting any caller.
• wrap(token, amount) escrows original tokens in the factory and mints the wrapped token 1:1 (mints the actually-received amount, so fee-on-transfer tokens can't inflate supply beyond backing). Only possible on the token's home chain.
• unwrap(token, amount) burns wrapped tokens and releases escrow.
• The wrapped token is a standard SuperchainERC20: crosschainMint/crosschainBurn are gated to the SuperchainTokenBridge, so once deployed on two chains, sendERC20/relayERC20 move it between them. Escrow on the home chain always equals global wrapped supply.

Notes for reviewers

• The revive commit restores the bridge byte-for-byte where possible; the only source adaptations are the solady import path (the versioned @solady-v0.0.245 remapping no longer exists; the vendored solady is v0.0.158) and registration in the new predeploy registry.
• L2ContractsManager semver bumped 1.13.0 → 1.14.0.
• Rebasing tokens are not supported by the wrap/unwrap escrow (negative rebases can strand late unwrappers), same caveat as any escrow wrapper.

Tests

• Restored SuperchainTokenBridge and SuperchainERC20 unit tests.
• New suites for the factory (deterministic addresses, home/remote metadata, propagate/relayDeploy auth + source-chain checks, wrap/unwrap, fee-on-transfer, escrow accounting) and the wrapped token (factory/bridge mint-burn gating, ERC7802 interface).

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