fix(cubesql): Make zero members wrapper more expensive than filter member

Author: mcheshkov

rust/cubesql/cubesql/src/compile/rewrite/cost.rs

@@ -234,6 +234,7 @@ impl BestCubePlan {
 /// - `empty_wrappers` > `non_detected_cube_scans` - we don't want empty wrapper to hide non detected cube scan errors
 /// - `non_detected_cube_scans` > other nodes - minimize cube scans without members
 /// - `filters` > `filter_members` - optimize for push down of filters
+/// - `zero_members_wrapper` > `filter_members` - prefer CubeScan(filters) to WrappedSelect(CubeScan(*), filters)
 /// - `filter_members` > `cube_members` - optimize for `inDateRange` filter push down to time dimension
 /// - `member_errors` > `cube_members` - extra cube members may be required (e.g. CASE)
 /// - `member_errors` > `wrapper_nodes` - use SQL push down where possible if cube scan can't be detected
@@ -259,12 +260,12 @@ pub struct CubePlanCost {
     wrapped_select_ungrouped_scan: usize,
     filters: i64,
     structure_points: i64,
-    filter_members: i64,
     // This is separate from both non_detected_cube_scans and cube_members
     // Because it's ok to use all members inside wrapper (so non_detected_cube_scans would be zero)
     // And we want to select representation with less members
     // But only when members are present!
     zero_members_wrapper: i64,
+    filter_members: i64,
     cube_members: i64,
     errors: i64,
     time_dimensions_used_as_dimensions: i64,