Handle NUL bytes in CSV query result export

[keerthanapadige]

• Bug Fix

Description

Fixes CSV export failure when query result string values contain embedded NUL bytes (\x00).

Previously, serialize_query_result_to_dsv() passed row values directly to csv.DictWriter.writerow(). If a string field contained a NUL byte, CSV export could fail with:

_csv.Error: need to escape, but no escapechar set

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[cubic-dev-ai]

No issues found across 2 files

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