Route app messages to the blockchain

[mkysel]

Route app messages to the blockchain by removing IsCommit field from AuthenticatedData and implementing commit detection through message deserialization in the payer service

The system removes the IsCommit field from the AuthenticatedData structure and modifies commit detection to use message deserialization instead of authenticated data flags. The changes include:

• Remove IsCommit field from AuthenticatedData in pkg/proto/xmtpv4/envelopes/envelopes.pb.go and update related test helpers
• Modify shouldSendToBlockchain and determineRetentionPolicy functions in pkg/api/payer/service.go to use deserializer.IsGroupMessageCommit() for commit detection
• Update publishToBlockchain function to use constants from contracts package for originator IDs instead of hardcoded values
• Remove TestPublishCommitIsRejected test indicating commits are no longer rejected during publishing
• Update protobuf definitions to rename EncryptedCommitLogEntry to SerializedCommitLogEntry and add signature fields
• Add CommitLogSigner field to GroupMutableMetadataV1 for storing ED25519 private keys

📍Where to Start

Start with the shouldSendToBlockchain function in pkg/api/payer/service.go to understand how commit detection has changed from using the IsCommit field to message deserialization.

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Macroscope summarized a459911.

[graphite-app]

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