feat: flightsql initial support

[universalmind303]

example usage

pip install adbc_driver_flightsql
pip install polars

# example.py
import adbc_driver_flightsql.dbapi
import polars as pl

with adbc_driver_flightsql.dbapi.connect("grpc://0.0.0.0:6789") as conn:
    cursor = conn.cursor()
    cursor.execute(
        "SELECT * from './testdata/csv/userdata1.csv'"
    )
    res = cursor.fetch_arrow_table()
    print(pl.from_arrow(res))
    cursor.close()

See the official adbc flightsql docs for more info

[tychoish]

nothing seems out of place.

@vrongmeal (et al) should take a look to make sure that the consumption metrics stuff is properly wired up (but that need not happen during this pr.

[vrongmeal]

@vrongmeal (et al) should take a look to make sure that the consumption metrics stuff is properly wired up (but that need not happen during this pr.

Metrics are not being collected here. Looking more into the PR on how this might be easier to plug-in.

[vrongmeal]

Apart from metrics collection, this looks good to me! 🚀

[universalmind303]

@vrongmeal, I added a followup issue for setting up metrics