Document /v1/query api

### Is your proposal related to a problem?

The console uses the /v1/query api to fetch and modify rows. This api is not documented.

**Note** this is not about the use of `run_sql` used for things like fetching information on database structure. That uses the `/v2/query` api.

### Describe the solution you'd like

The api should be documented.

### Describe alternatives you've considered

Alternatively, the use of this api should be deprecated alongside the api itself.

This is tracked in #8986

Start by reviewing how the console uses the /v1/query API to fetch and modify rows, and compare that scope with the /v2/query distinction described in the issue. Check the related tracking issue #8986 before starting. Done means the /v1/query behavior is documented, or its deprecation status is clarified.

Written by the indexing model from the issue text.