Function evaluate_spatial_function 

pub fn evaluate_spatial_function(
    name: &str,
    args: &[Value],
    _coordinate_dim: usize,
) -> Result<Value>

Evaluate a spatial (ST_*) function call.

The dispatch is case-insensitive on name. Returns a typed Value on success or a typed QueryError on failure (invalid arity, unparseable WKT, unsupported predicate for the given geometry types, …).

_coordinate_dim is reserved for a future 3-D/M extension; the current implementation operates strictly on 2-D f64 geometries.