Document: refactor: allow modification of the query mode

[neverchanje]

This issue tracks the documentation update needed for the merged PR #19424.

Source PR URL: risingwavelabs/risingwave#19424
Source PR Merged At: 2024-11-19T10:01:38Z

If it is a major improvement that deserves a new page or a new section in the documentation, please check if we should label it as an experiment feature.