GeezerVison

Fixes #472 (point 1)

TransformationExecution only declared id and created_at, so hookdeck gateway transformation executions list|get --output json dropped everything else the API returns for an execution (original_event_data, transformed_event_data, logs, log_level, webhook_id, issue_id).

Fix: add those fields to the struct. The event payloads and logs are json.RawMessage, so their shape is passed through unchanged; scalar fields are omitempty so nothing new appears when the API omits them.

Test: TestTransformationExecution_KeepsAPIFields decodes a full execution body and checks all six fields survive re-encoding. It fails to build before the change and passes after.

Only point 1 of the issue is addressed here.

Disclosure: this change was prepared with an AI coding agent (Claude).