Complete PolygonMesh, PolyfaceMesh and Mesh host model coverage

Maps all three mesh kinds with host validation of grid counts, face indices
and edge topology, and skips sub-record common data in the generator.
A shared run_mesh_lifecycle driver passes the full gate for each kind,
including DWG and DXF reopen with re-edit.

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

plugins/opencad-python/entity_manifest.json

@@ -26,7 +26,10 @@
     "MLine",
     "Dimension",
     "MultiLeader",
-    "Table"
+    "Table",
+    "PolygonMesh",
+    "PolyfaceMesh",
+    "Mesh"
   ],
   "manual_kinds": ["Dimension"],
   "base_fields": ["handle", "layer", "owner_handle"],
@@ -310,6 +313,24 @@
         "legacy_border_line_weights": { "exclude": true },
         "legacy_border_visibility": { "exclude": true }
       }
+    },
+    "PolygonMesh": {
+      "rust_constructor": "acadrust::entities::PolygonMeshEntity::default()",
+      "fields": { "vertices": { "required": true } }
+    },
+    "PolyfaceMesh": {
+      "fields": {
+        "vertices": { "required": true },
+        "faces": { "required": true },
+        "seqend_handle": { "read_only": true }
+      }
+    },
+    "Mesh": {
+      "fields": {
+        "vertices": { "required": true },
+        "faces": { "required": true },
+        "version": { "read_only": true }
+      }
     }
   }
 }