Commitment mechanism change

[dusannosovic-ethernal]

Description

This PR introduces the following changes:

1. Validator Set Changes: Validator set changes are now sent as state transactions to the BridgeStorage contract at the end of each epoch.
2. Batch Transactions: Batches are sent as state transactions to the BridgeStorage contract at the end of each sprint.
3. Signature Mechanism Update: The signature mechanism has been updated so that validators now sign batches.

BridgeMessageStore Bucket Organization Changes:

bridgeMsgEvents

• chainId/ → bridgeMessageEvent.Id/ → *BridgeMsgEvent (JSON marshalled)

bridgeBatch

• chainId/ → bridgeBatches.Message[last].Id/ → *BridgeBatchSigned (JSON marshalled)

relayerEvents

• chainId/ → RelayerEventData.EventID/ → *RelayerEventData (JSON marshalled)

Struct Name Changes:

• PendingCommitment → PendingBridgeBatch
• CommitmentMessageSigned → BridgeBatchSigned

File Name Changes:

• state_sync_manager.go → bridge_events_manager.go
• state_sync_commitment.go → bridge_batch.go
• state_sync_state_store.go → state_sync_bridge_store.go

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Breaking changes

Please complete this section if any breaking changes have been made, otherwise delete it

Checklist

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually