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Description

Dataset query history writes created_by_role from multiple paths (app retrieval, tool callbacks, hit testing) with inconsistent role value formats. This results in mixed role strings in the dataset query table and complicates downstream filtering or analytics.

Motivation

Consistent role values are required for reliable dataset query history analysis and user-facing filtering.

Additional Context

Clarify the source-of-truth enum/value format for dataset query created_by_role and normalize all write paths to the same representation.