MULTIPOINT present in output of preprocessed ften road section lines

```
$ ogrinfo /vsis3/$BUCKET/sources/whse_forest_tenure.ften_road_section_lines_svw.parquet -dialect SQLite -sql "SELECT DISTINCT GeometryType(geometry) AS gtype FROM \"whse_forest_tenure.ften_road_section_lines_svw\""

Layer name: SELECT
Geometry: None
Feature Count: 2
Layer SRS WKT:
(unknown)
gtype: String (0.0)
OGRFeature(SELECT):0
gtype (String) = MULTILINESTRING

OGRFeature(SELECT):1
gtype (String) = MULTIPOINT
```

No source file or test is named. Start by rerunning the ogrinfo query against the preprocessed whse_forest_tenure.ften_road_section_lines_svw.parquet dataset, then trace the repository's preprocessing entry point to find where the MULTIPOINT geometry is introduced. Done means the output contains the intended road geometry types without MULTIPOINT.

Written by the indexing model from the issue text.