Count: measured messages and listing, groups, Current area, boundary checks, fills and solids recoloured

- COUNTCOLOR / COUNTERRORCOLOR / COUNTSERVICE reject any other value with
  the range message; COUNTTABLE ? lists in the reference order, padded,
  22 lines a page with Press ENTER to continue:, then the totals.
- Target picks report N found / N found, M total; several objects (or one
  that is not a block reference) count their copies, shown as Geometries
  in the palette.
- Current area is the area in use (kept aside by Entire model space),
  otherwise all of model space; an invalid Object boundary ends with the
  reference message.
- Count colours reach solids and fills; the palette list and the count
  are recomputed only when the drawing changes.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/scene/entity.rs

@@ -1451,6 +1451,7 @@ impl Scene {
                         }
                     }
                 }
+                m.color = self.count_color(handle, m.color, self.current_bg());
                 if tint_selected && self.selected.contains(&handle) {
                     m.color = [0.15, 0.55, 1.00, m.color[3]];
                 }
@@ -1752,6 +1753,7 @@ impl Scene {
                         )
                     });
                 }
+                model.color = self.count_color(context.root_handle, model.color, hatch_bg);
                 if tint_selected && self.selected.contains(&context.root_handle) {
                     model.color = [0.15, 0.55, 1.00, model.color[3]];
                 }