feat: preserve body history and placed modelling workflows

Record ownership transfers in the timeline so earlier Join/Cut membership,
world placement, machining data and styles survive component moves, edits,
independent copying, undo and reopening. Preserve pending positions in history
snapshots and keep constructor transfers ordered during feature redefinition.

Retain shallow sheet pockets and exact planar intersection islands through
unfold/refold, with depth-aware flat previews and DXF export. Store explicit
3D wire coordinate spaces and migrate known legacy provenance without moving
saved points or analytic fits.

Infer unique eligible cylindrical Emboss targets, align Revolve manipulators
with actual extent geometry, and discard obsolete preview errors after input
correction. Certify constructed and immutable imported face styles using exact
source metadata while preserving legacy face names. Upgrade designs to format10
with bounded validation and geometry-preserving legacy migration.

README.md

@@ -39,9 +39,12 @@ and help is welcome: see [CONTRIBUTING.md](CONTRIBUTING.md).
 - **Parameters and configurations** with unit-aware expressions (`2 * width + 5 mm`,
   `angle / 2`), ordered rules, feature suppression and per-row body materials/appearances.
 - **Assemblies** with nested components and occurrences, joints, motion studies, contact sets,
-  interference and material-aware mass properties.
+  interference and material-aware mass properties. Recorded body transfers preserve modelling
+  history and world placement; 3D sketch wires retain their coordinate frames through edits.
 - **Sheet metal** with flanges, hems, fold/unfold/refold, material cutouts, flat patterns,
-  exact line/arc/circle DXF outlines and bend tables; plastic enclosure features and rules.
+  retained shallow prismatic pockets, exact line/arc/circle DXF outlines and bend tables;
+  plastic enclosure features and rules. Pocket depth and side survive unfold/refold and appear
+  separately from through-hole outlines in the flat preview and DXF.
 - **Files**: designs as JSON (`.solvecraft`), export to STEP (AP242 with body names, colours and
   components as assemblies; revolved faces as native planes, cylinders, cones, spheres and tori),
   IGES 5.3 (manifold solid B-reps with names and colours), 3MF, STL (binary/ASCII) and OBJ;