Add kernel solid operations and complete Solid3D (create and rigid move)

An additive HostApi::solid_operation builds cadkernel primitives and applies
rigid transforms, verifying each result lifts back losslessly and refusing a
payload it cannot lift. Exposed as doc.solids in Python; Solid3D, Body and
Region are mapped read-only with the opaque payload preserved. The lifecycle
test passes through the real runner with analytic volumes and exact extents as
oracles, DWG and DXF reopen with re-edit, and undo restores exactly.

Co-Authored-By: Claude Sonnet 5 <[email protected]>

crates/ocs_plugin_api/src/entity_coverage.rs

@@ -2532,6 +2532,9 @@ mod tests {
                         | "ViewBorder"
                         | "Light"
                         | "Ole2Frame"
+                        | "Solid3D"
+                        | "Body"
+                        | "Region"
                 )
             {
                 assert!(