Fix bug with the first object rename after class assignment

The problem was that during class assignment, it was setting the object name and `is_renaming` flag but only then linking to IFC. Since object wasn't linked to IFC, name callback wasn't triggered and `is_renaming` wasn't reset and first rename wouldn't work.
Now it's just not setting the flag if object is not linked to IFC, as there's no callback then and don't need to protect from it.

src/bonsai/bonsai/bim/prop.py

@@ -620,7 +620,14 @@ class BIMObjectProperties(PropertyGroup):
     )
     cartesian_point_offset: StringProperty(name="Cartesian Point Offset")
     is_reassigning_class: BoolProperty(name="Is Reassigning Class")
-    is_renaming: BoolProperty(name="Is Renaming", default=False)
+    is_renaming: BoolProperty(
+        name="Is Renaming",
+        description=(
+            "Flag to ensure object name callback wouldn't write new name to IFC. "
+            "Automatically reset to `False` after the next callback."
+        ),
+        default=False,
+    )
     location_checksum: StringProperty(name="Location Checksum")
     rotation_checksum: StringProperty(name="Rotation Checksum")
 

src/bonsai/bonsai/tool/root.py

@@ -419,7 +419,9 @@ class Root(bonsai.core.tool.Root):
         name = tool.Loader.get_name(element)
         if obj.name != name:
             props = tool.Blender.get_object_bim_props(obj)
-            props.is_renaming = True
+            # If it's not an IFC object, then it doesn't have a name callback.
+            # So, we need to protect it writing to IFC.
+            props.is_renaming = bool(tool.Ifc.get_entity(obj))
             obj.name = name  # The handler will trigger, and reset is_renaming to False
 
     @classmethod
@@ -428,7 +430,7 @@ class Root(bonsai.core.tool.Root):
         if material.name == name:
             return
         msprops = tool.Style.get_material_style_props(material)
-        msprops.is_renaming = True
+        msprops.is_renaming = bool(tool.Ifc.get_entity(material))
         material.name = name  # The handler will trigger, and reset is_renaming to False.
 
     @classmethod