Use Content-Type application/x-ndjson for JSONEachRow Output Format

Why it matters

This feature enables better compatibility with tools and services that expect newline-delimited JSON (NDJSON) by explicitly setting the appropriate Content-Type header when ClickHouse outputs data using the JSONEachRow format. It improves integration and data interchange scenarios involving NDJSON.

How to use it

When querying ClickHouse with the output format set to JSONEachRow, the HTTP response will include the Content-Type: application/x-ndjson header, signaling that the output follows the NDJSON specification. No additional configuration is required from the user side.