This updates the v1 /query API hanlder to handle InfluxDB v1's unique
query response structure when GROUP BY clauses are provided.
The distinction is in the addition of a "tags" field to the emitted series
data that contains a map of the GROUP BY tags along with their distinct
values associated with the data in the "values" field.
This required splitting the QueryExecutor into two query paths for InfluxQL
and SQL, as this allowed for handling InfluxQL query parsing in advance
of query planning.
A set of snapshot tests were added to check that it all works.
This ended up being a couple things rolled into one. In order to add a query API to the Python plugin, I had to pull the QueryExecutor trait out of server into a place so that the python crate could use it.
This implements the query API, but also fixes up the WAL plugin test CLI a bit. I've added a test in the CLI section so that it shows end-to-end operation of the WAL plugin test API and exercise of the entire Plugin API.
Closes#25757
Trevor Hilton
Paul Dix