feat: http api csv

[zeroslope]

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What's changed and what's your intention?

#577 add csv format support for /sql api.

For the format of the return value.

1. first use query param "format=", optional values are json, csv
2. second use Accept Header, optional values are Accept: application/json or Accept: application/csv
3. If neither is available, the default value (csv) is used.

For stream, if query param "chunked=false" is passed, then streaming is not applicable, otherwise streaming is enabled by default.

Please explain IN DETAIL what the changes are in this PR and why they are needed:

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• How does this PR work? Need a brief introduction for the changed logic (optional)
• Describe clearly one logical change and avoid lazy messages (optional)
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Checklist

• [] I have written the necessary rustdoc comments.
• [] I have added the necessary unit tests and integration tests.

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