fix(model): restore saved solid booleans

Reload exact B-reps from solid history or ACIS before model operations and pin the closed-cut kernel fix.

src/scene/convert/solid3d_tess.rs

@@ -1,5 +1,6 @@
 use acadrust::entities::acis::{SabReader, SatBody, SatDocument};
 use acadrust::entities::{Body, Region, Solid3D};
+use cadkernel::brep::{self, Body as KernelBody};
 
 use crate::scene::model::mesh_model::{MeshLodSet, MeshModel};
 
@@ -154,6 +155,33 @@ fn parse_acis(
     })
 }
 
+pub fn kernel_body(solid: &Solid3D) -> Option<KernelBody> {
+    let sat = parse_acis(
+        || solid.parse_sat(),
+        solid.acis_data.is_binary,
+        &solid.acis_data.sab_data,
+    )?;
+    let (mut bodies, loss) = cadkernel::acis::lift(&sat);
+    if !loss.is_empty() || bodies.len() != 1 {
+        return None;
+    }
+    let body = bodies.pop()?;
+    let source = body.provenance.source()?;
+    let Some((matrix, translation, scale)) = body_transform(&sat, source.index() as usize).ok()?
+    else {
+        return Some(body);
+    };
+    brep::transform(
+        &body,
+        &brep::Placement {
+            x_axis: [scale * matrix[0], scale * matrix[1], scale * matrix[2]],
+            y_axis: [scale * matrix[3], scale * matrix[4], scale * matrix[5]],
+            z_axis: [scale * matrix[6], scale * matrix[7], scale * matrix[8]],
+            origin: translation,
+        },
+    )
+}
+
 fn remap_acis_material_bindings(
     set: &mut MeshLodSet,
     acis: &acadrust::entities::AcisData,

src/scene/entity.rs

@@ -586,11 +586,28 @@ impl Scene {
             self.images.insert(handle, model);
         }
         self.refresh_meshes_for_handles(&[handle]);
-        if let Some(operation) = self.document.solid_history_operation(handle).cloned() {
-            if let Ok(body) = cadkernel::acis::rebuild_body(&operation) {
-                self.solid_models.insert(handle, body);
-            }
-        }
+        self.restore_solid_models(&[handle]);
+    }
+
+    pub fn restore_solid_models(&mut self, handles: &[Handle]) {
+        let bodies: Vec<(Handle, cadkernel::brep::Body)> = handles
+            .iter()
+            .filter(|handle| !self.solid_models.contains_key(handle))
+            .filter_map(|&handle| {
+                let from_history = self
+                    .document
+                    .solid_history_operation(handle)
+                    .and_then(|operation| cadkernel::acis::rebuild_body(operation).ok());
+                let body = from_history.or_else(|| match self.document.get_entity(handle) {
+                    Some(EntityType::Solid3D(solid)) => {
+                        crate::scene::convert::solid3d_tess::kernel_body(solid)
+                    }
+                    _ => None,
+                })?;
+                Some((handle, body))
+            })
+            .collect();
+        self.solid_models.extend(bodies);
     }
 
     /// Re-tessellate only the named ACIS entities. The former edit path

src/scene/mod.rs

@@ -1645,11 +1645,7 @@ pub struct Scene {
     /// owning block emits a transformed instance so a block placed at an
     /// INSERT scale renders at the right size. (#123)
     pub block_meshes: HashMap<Handle, MeshLodSet>,
-    /// Live B-reps for solids created this session by the Model tab, keyed by
-    /// entity handle. Backs the Design-group boolean tools (a solid must be
-    /// here to be combined) and the exact-geometry save path, which writes
-    /// each one back out as ACIS rather than as facets. Not persisted —
-    /// rebuilt only by creating or combining primitives in-session.
+    /// Kernel B-reps used by solid operations and exact-geometry saves.
     pub solid_models: HashMap<Handle, cadkernel::brep::Body>,
     /// GPU render data for raster images (RasterImage entities), keyed by handle.
     pub images: HashMap<Handle, ImageModel>,