Engine: geometry.datum, geometry.datum.axis and geometry.partition

Datum planes by principal plane and offset, three points, or point and
normal; datum axes by principal axis, two points, or point and direction.
geometry.partition cuts the open design by a datum plane and keeps the
partition in the model, so geometry.open, file.open and undo cut the design
again. Requirements, forms and the Prepare entries are wired; features.md
lists them as ready.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo

crates/engine/src/catalogue.rs

@@ -232,8 +232,22 @@ pub static CATALOGUE: &[Capability] = &[
         "Inspect",
         "Weld, closed, manifold, orientation and self-intersection checks; feature edges",
     ),
-    soon("geometry.partition", "Partition", Geometry, "Prepare", "M5", "Split bodies and faces as SolidCraft features"),
-    soon("geometry.datum", "Datum Plane", Geometry, "Prepare", "M5", "Construction planes for partitions"),
+    ready_more(
+        "geometry.datum",
+        "Datum Plane",
+        Geometry,
+        "Prepare",
+        "Datum planes (principal plane and offset, three points, point and normal) and axes",
+        &["geometry.datum.axis", "geometry.datum.delete"],
+    ),
+    ready_more(
+        "geometry.partition",
+        "Partition",
+        Geometry,
+        "Prepare",
+        "Cut bodies into cells by a datum plane; the two faces of each cut are paired by name",
+        &["geometry.partition.delete"],
+    ),
     soon("geometry.midsurface", "Midsurface", Geometry, "Prepare", "M8", "Extract midsurfaces of thin parts for shell meshes"),
     // ---- Mesh ----
     soon("mesh.size.global", "Global Size", Mesh, "Size", "M2", "One element size for the whole part"),