feat(properties): fill solid-history + viewport clipped rows

Bump acadrust to ef0e231 (region/body history handle + viewport clip
boundary now stored) and populate the rows the builders left blank:

- Solid3D / Body "Show History": derived from the history handle's
  presence (there is no separate stored bool — the DWG carries only the
  H 350 history link).
- Body "History": the history handle, matching how Solid3D already shows
  it.
- Viewport "Clipped": Yes when the clip-boundary handle is non-NULL.

Hatch Origin X/Y and Boundary retention stay blank by design: they are
not part of the persisted AcDbHatch record in DWG or DXF (retention is a
BHATCH command setting), so there is nothing to read.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/entities/viewport.rs

@@ -129,7 +129,11 @@ fn properties(vp: &Viewport) -> Vec<PropSection> {
                         value: vp.status.is_on,
                     },
                 },
-                ro("Clipped", "vp_clipped", String::new()),
+                ro(
+                    "Clipped",
+                    "vp_clipped",
+                    if vp.clip_boundary_handle.is_null() { "No" } else { "Yes" },
+                ),
                 Property {
                     label: "Display locked".into(),
                     field: "vp_locked",