Complete Surface: plane surfaces, extrusions, isolines and moves

Adds SurfaceFromProfile and Extrude kernel operations (doc.solids.surface and
doc.solids.extrude), accepts surfaces in Transform, and maps Surface with
editable isolines. Fixes a real bug found by the test: the surface kind field
overwrote the entity-type kind key in Python dicts, so it is exposed as
surface_kind, with a catalog test guarding against name collisions.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

docs/plugin-host-model.md

@@ -35,7 +35,7 @@ attached attribute and sequence records. Those fields report `transaction_geomet
 catalog. All 43 canvas kinds also support nonempty `layer` changes through
 the same undoable transaction; internal and opaque variants remain read-only
 through the document model. The adapter accepts only `layer` patches for
-canvas kinds outside its 41 geometry converters. Other writable properties
+canvas kinds outside its 42 geometry converters. Other writable properties
 still report `type_conversion_only`; broader CAD range and cross-property
 checks remain outstanding.
 The host's `entity_snapshot` helper serializes any typed entity as a detached
@@ -92,7 +92,7 @@ Input tokens are bound to the drawing tab that requested the pick. Polling a
 token from another tab returns no result and does not consume it.
 
 Python `doc.entities[handle]` returns a descriptor for every entity. For kinds
-outside the 41-kind generated schema it contains only handle, kind, and layer;
+outside the 42-kind generated schema it contains only handle, kind, and layer;
 `layer` is editable on canvas kinds. `doc.coverage()` enumerates the
 catalog; `doc.coverage("Line")` and `line.coverage` return one entry. For
 covered kinds, the coverage object lists actual readable and editable