Fix: Set position node doesn't tag mesh normals dirty

Caused by b08301c865. This also contains an optimization
compared to the previous version to avoid recalculating normals when
the entire mesh has moved by the same offset.

Reported by Demeter in chat.

source/blender/nodes/geometry/nodes/node_geo_set_position.cc

@@ -54,6 +54,12 @@ static void set_computed_position_and_offset(GeometryComponent &component,
                 }
               });
         });
+        if (in_offsets.is_single() && selection.size() == verts.size()) {
+          BKE_mesh_tag_coords_changed_uniformly(mesh);
+        }
+        else {
+          BKE_mesh_tag_coords_changed(mesh);
+        }
       }
       else {
         devirtualize_varray2(
@@ -66,6 +72,7 @@ static void set_computed_position_and_offset(GeometryComponent &component,
                     }
                   });
             });
+        BKE_mesh_tag_coords_changed(mesh);
       }
       break;
     }