st_read with only non-geometry columns still reads geometry

A bit of an edge case I ran into. We received data as geopackage, with Curve geometries. This can not be read by DuckDB spatial. I used ogr2ogr to converth the GPKG file to a GeoParquet file, which works fine (although curve support would be awesome). Then I wan to do a simple count of the numbers of records, to be sure the conversion worked:

`SELECT COUNT(fid) FROM st_read('my-geopackage.gpkg')`

The fid column is an integer column. In this scenario, there is no need to read the geometry of the geopackage. Yet it throws the following error:
`Exception has occurred: InvalidInputException Invalid Input Error: Unsupported geometry type in WKB`. It would be nice if the query could still work and I think it would enhance performance if st_read only reads geometry when it is absolutely necessary.

I'm running this on 1.5.4 of DuckDB by the way.

Start by reproducing the `SELECT COUNT(fid) FROM st_read('my-geopackage.gpkg')` query with a GeoPackage containing Curve geometries. Trace the `st_read` entry point and its column-reading path to determine why geometry is decoded when only `fid` is selected. Done means the count query succeeds without requiring unsupported geometry handling, while geometry-reading queries retain their existing behavior.

Written by the indexing model from the issue text.