feat(l2): shared bridge forced inclusion

[avilagaston9]

Motivation

In a shared bridge environment, we need a way to enforce L2s to include messages from other L2s.
We take the same approach as with deposits:

• After some time, a message is considered expired if it has not yet been included in a batch.
• When this happens, the sequencer is prevented from including non-privileged transactions until all expired messages are included.

Description

• Adds the forced inclusion mechanism to the documentation.
• Modifies l1_committer to commit the l2_out_message_hashes and the rolling hash of received processed messages in the batch.
• Modifies the Batch struct:
  • Adds the l2_in_message_rolling_hashes field.
  • Removes l2_message_hashes, since they are now included in the BalanceDiff struct.
• Removes all l2_messages_merkle_root related logic. Since we now send all message hashes, the Merkle root is no longer needed.
• Renames privileged transactions | deposits to l1_in_messages throughout the codebase. A privileged transaction represents a message from another chain (L1 or L2). deposits was also being used to refer to L1 inbound messages, but messages can be more than simple deposits.
• Updates the prover to output L2RollingHashes.
• Restores blobs due to changes in the L2 genesis.

[Copilot]

Pull request overview

This PR implements forced inclusion of cross-chain messages for shared bridge environments. The core change ensures L2s cannot avoid processing messages from other L2s by preventing commitment of batches with non-privileged transactions until all expired messages are included. The implementation tracks message hashes per source chain and validates their inclusion through rolling hashes computed by the prover.

Key changes:

• Introduces forced inclusion mechanism where expired messages block non-privileged transaction inclusion
• Replaces merkle root verification with direct message hash tracking and rolling hash validation
• Renames privileged transaction terminology from "deposits" to "l1_in_messages" and "l2_in_messages" for clarity

Reviewed changes

Copilot reviewed 43 out of 50 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
docs/l2/fundamentals/shared_bridge.md	Documents forced inclusion mechanism and updated cross-chain message flow
crates/networking/p2p/rlpx/l2/messages.rs	Updates Batch serialization to include rolling hashes and remove merkle roots
crates/l2/utils/state_reconstruct.rs	Refactors batch reconstruction to compute rolling hashes for L1/L2 inbound messages
crates/l2/utils/error.rs	Adds error variants for privileged transaction and integer conversion failures
crates/l2/tests/shared_bridge.rs	Adds test verifying forced inclusion prevents batch verification
crates/l2/storage/src/store_db/sql.rs	Updates database schema to store rolling hashes and non-privileged transaction counts
crates/l2/storage/src/store_db/in_memory.rs	Updates in-memory storage to match SQL store changes
crates/l2/storage/src/store.rs	Updates store API to retrieve rolling hashes instead of message lists
crates/l2/storage/src/api.rs	Updates storage API signatures for rolling hash access
crates/l2/sequencer/l1_watcher.rs	Changes message verification from merkle proofs to pending message hash checks
crates/l2/sequencer/l1_committer.rs	Updates batch commitment to include rolling hashes and message hash lists
crates/l2/sequencer/errors.rs	Adds error for invalid privileged transactions
crates/l2/sequencer/block_producer/payload_builder.rs	Removes chain-specific privileged transaction filtering
crates/l2/sdk/src/sdk.rs	Adds functions to query pending L2 messages and removes message verification
crates/l2/sdk/contract_utils/src/compile.rs	Enables Solidity optimizer to manage bytecode size
crates/l2/prover/src/guest_program/src/output.rs	Updates prover output to include rolling hashes instead of merkle roots
crates/l2/prover/src/guest_program/src/execution.rs	Refactors prover to compute rolling hashes for message validation
crates/l2/networking/rpc/rpc.rs	Adds RPC endpoint for batch lookup by block number
crates/l2/networking/rpc/l2/messages.rs	Removes L2 message proof generation RPC method
crates/l2/networking/rpc/l2/batch.rs	Adds handler for batch retrieval by block number
crates/l2/networking/rpc/clients.rs	Updates client to support batch retrieval by block
crates/l2/monitor/widget/l1_to_l2_messages.rs	Updates widget to use renamed pending messages function
crates/l2/monitor/widget/batches.rs	Updates batch display to use renamed message hash field
crates/l2/docker-compose.yaml	Adds log level environment variable configuration
crates/l2/contracts/src/l1/interfaces/IRouter.sol	Updates router interface to send multiple message hashes
crates/l2/contracts/src/l1/interfaces/IOnChainProposer.sol	Updates proposer interface for rolling hash commitment
crates/l2/contracts/src/l1/interfaces/ICommonBridge.sol	Updates bridge interface for message hash tracking
crates/l2/contracts/src/l1/based/interfaces/IOnChainProposer.sol	Adds non-privileged transaction count to based proposer interface
crates/l2/contracts/src/l1/based/OnChainProposer.sol	Implements forced inclusion check in based proposer
crates/l2/contracts/src/l1/Router.sol	Implements multi-hash message sending and removes merkle verification
crates/l2/contracts/src/l1/OnChainProposer.sol	Implements rolling hash verification and forced inclusion enforcement
crates/l2/contracts/src/l1/CommonBridge.sol	Implements message hash tracking and expiration checking
crates/l2/common/src/privileged_transactions.rs	Adds function to extract L2 inbound messages from transactions
crates/l2/common/src/messages.rs	Updates L2Message structure and encoding to include source chain ID
crates/l2/based/block_fetcher.rs	Adds chain_id parameter to batch reconstruction
crates/common/types/transaction.rs	Includes chain_id in privileged transaction hash computation
crates/common/types/l2/batch.rs	Updates Batch structure with rolling hashes
crates/common/types/l2/balance_diff.rs	Adds message_hashes field to BalanceDiff
cmd/ethrex/l2/deployer.rs	Updates bridge initialization with chain_id parameter
cmd/ethrex/l2/command.rs	Passes chain_id to batch reconstruction
cmd/ethrex/cli.rs	Adds environment variable support for log level
.github/workflows/pr-main_l2.yaml	Adds forced inclusion test matrix and debug logging
.github/workflows/pr-main_l1_l2_dev.yaml	Fixes environment file location for tests

Comments suppressed due to low confidence (4)

crates/l2/tests/shared_bridge.rs:1

• Use line.starts_with('#') with a character literal instead of a string literal for better performance and idiomatic code.
  crates/l2/tests/shared_bridge.rs:1
• Corrected spelling of 'porpuse' to 'purpose'.
  crates/l2/sequencer/l1_committer.rs:1
• The function signature string spans multiple lines. Consider keeping it on a single line or using a more readable format to improve maintainability.
  crates/l2/storage/src/store_db/sql.rs:1
• Corrected spelling of 'pendinL2MessagesLength' to 'pendingL2MessagesLength' in function call.

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[ManuelBilbao]

RUST_LOG does the job too

[JereSalo]

Here when encoding an L2Message we are not encoding the dest_chain_id. Can this be a problem given that when getting the L2 Message hash we do keccak(msg.encode())? I mean, 2 equal messages to different L2s could possibly have the same hash. Is that a problem or is it intentional?