Fix add_georeferencing silently failing with orphan CRS or conversion

If a file had an IfcProjectedCRS without an IfcCoordinateOperation (or
vice versa), add_georeferencing would return early without creating the
missing entity. This caused edit_georeferencing to crash with IndexError.
Now detects the inconsistent state, cleans up, and recreates both.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/ifcopenshell-python/ifcopenshell/api/georeference/add_georeferencing.py

@@ -17,6 +17,7 @@
 # along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
 
 import ifcopenshell
+import ifcopenshell.api.georeference
 import ifcopenshell.api.pset
 import ifcopenshell.util.element
 
@@ -63,8 +64,13 @@ def add_georeferencing(file: ifcopenshell.file, ifc_class: str = "IfcMapConversi
             },
         )
         return
-    if file.by_type("IfcProjectedCRS"):
+    has_crs = bool(file.by_type("IfcProjectedCRS"))
+    has_conversion = bool(file.by_type("IfcCoordinateOperation"))
+    if has_crs and has_conversion:
         return
+    if has_crs or has_conversion:
+        # This is technically invalid, but we shall forgive the industry here if they are wrong ...
+        ifcopenshell.api.georeference.remove_georeferencing(file)
     source_crs = None
     for context in file.by_type("IfcGeometricRepresentationContext", include_subtypes=False):
         if context.ContextType == "Model":

src/ifcopenshell-python/test/api/georeference/test_add_georeferencing.py

@@ -51,6 +51,30 @@ class TestAddGeoreferencing(test.bootstrap.IFC4):
         assert len(self.file.by_type("IfcMapConversion")) == 1
         assert len(self.file.by_type("IfcProjectedCRS")) == 1
 
+    def test_recovering_from_orphan_projected_crs(self):
+        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
+        ifcopenshell.api.context.add_context(self.file, "Model")
+        self.file.create_entity("IfcProjectedCRS", Name="EPSG:1234")
+        assert len(self.file.by_type("IfcProjectedCRS")) == 1
+        assert len(self.file.by_type("IfcCoordinateOperation")) == 0
+        ifcopenshell.api.georeference.add_georeferencing(self.file)
+        assert len(self.file.by_type("IfcMapConversion")) == 1
+        assert len(self.file.by_type("IfcProjectedCRS")) == 1
+
+    def test_recovering_from_orphan_coordinate_operation(self):
+        ifcopenshell.api.root.create_entity(self.file, ifc_class="IfcProject")
+        context = ifcopenshell.api.context.add_context(self.file, "Model")
+        self.file.create_entity("IfcMapConversion", SourceCRS=context, TargetCRS=self.file.create_entity("IfcProjectedCRS", Name="EPSG:1234"))
+        ifcopenshell.api.georeference.remove_georeferencing(self.file)
+        # Simulate orphan by re-adding just a conversion without CRS
+        self.file.create_entity("IfcMapConversion", SourceCRS=context, TargetCRS=self.file.create_entity("IfcProjectedCRS", Name="EPSG:1234"))
+        self.file.remove(self.file.by_type("IfcProjectedCRS")[0])
+        assert len(self.file.by_type("IfcProjectedCRS")) == 0
+        assert len(self.file.by_type("IfcCoordinateOperation")) == 1
+        ifcopenshell.api.georeference.add_georeferencing(self.file)
+        assert len(self.file.by_type("IfcMapConversion")) == 1
+        assert len(self.file.by_type("IfcProjectedCRS")) == 1
+
 
 class TestAddGeoreferencingIFC2X3(test.bootstrap.IFC2X3):
     def test_adding_georeferencing(self):