shapely: add tests reaching into deps numpy and geos

[MMesch]

Template B: Checklist for updating a package

• ⚠️ Bump build number if the version remains unchanged (2 → 3)

Package Details

• Package Name: shapely
• Version: 2.1.2 (build 3)

Build Notes

The previous test_shapely.py had two tests — test_import and test_basics. The latter's only assertion was a stray c == pytest.approx(1.0) expression (no assert), so it could not fail. Replace with six tests that go through shapely's declared runtime deps numpy and geos, ordered numpy → geos:

• test_import — loads shapely and shapely.lib native module.
• test_array_construction_with_numpy — shapely.points(np.ndarray) and get_coordinates roundtrip.
• test_predicates_and_measures_with_geos — is_valid, contains, area, length, distance (distinct GEOS*_r entrypoints).
• test_boolean_ops_with_geos — intersection, union, difference (overlay path — the surface PR libgdal-core: fix unresolved symbols; add tests; link geos and proj dynamically #6586 fixed in libgdal-core).
• test_buffer_and_simplify_with_geos — Point.buffer + LineString.simplify (Douglas-Peucker).
• test_wkt_roundtrip_with_geos — from_wkt / to_wkt reader/writer path.

No source or build.sh changes. Recipe change is limited to the build number bump.

[MMesch]

@IsabelParedes ready for review/merge. Just some basic tests that all pass.