Discuss what to do with the possible creation of invalid models #678
Description
Users can create invalid SynthML models in the UI.
When this happens, the UI does not crash or launches a popup window, but we get an error in the Eclipse console.
This applies for the new occurrence constraint stereotype (see discussion https://github.com/TNO/SynthML/pull/675/changes/BASE..c67a03ab16a747786d1e9648e6e7ab8c2e57ac4e#r2665472806) but it relates also to other UML elements -- possibly all stereotyped elements.
All these errors will be picked up by the validator, so a user will get the error message later on. Should we create something to signal the user that the model is invalid before the validation? If so, how to?