GraphQL equivalent API as REST "/v1/sql"?

[jychen7]

Is your feature request related to a problem? Please describe.
REST have /v1/sql API to get the SQL Code generated by Cube to be executed in the database.
https://cube.dev/docs/rest-api#api-reference-v-1-sql

However, for a GraphQL query, there seems no equivalent API. It is a nice to have feature, maybe helpful to debug whether the query is expected. e.g. #4387
(btw, playground may help, but for production, playground is normally turn off)

Describe the solution you'd like
GraphQL equivalent API as REST "/v1/sql". Still /graphql endpoint, but provide a different query type?

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.

[github-actions]

If you are interested in working on this issue, please leave a comment below and we will be happy to assign the issue to you.
If this is the first time you are contributing a Pull Request to Cube.js, please check our contribution guidelines.
You can also post any questions while contributing in the #contributors channel in the Cube.js Slack.