Fix originator in indexer storer

[mkysel]

Fix originator parameter passing in indexer storer buildOriginatorEnvelope functions for GroupMessageStorer and IdentityUpdateStorer

The buildOriginatorEnvelope functions in both group_message_storer.go and identity_update_storer.go now accept an explicit originatorId parameter instead of hardcoding the originator ID values internally. The corresponding test files group_message_storer_test.go and identity_update_storer_test.go add assertions to verify that the originator node ID in envelopes matches the expected constants GROUP_MESSAGE_ORIGINATOR_ID and IDENTITY_UPDATE_ORIGINATOR_ID respectively.

📍Where to Start

Start with the StoreLog method in group_message_storer.go to see how the modified buildOriginatorEnvelope function is called with the explicit originator ID parameter.

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Macroscope summarized 028fa37.

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