Added an interactive 'Add role' dialog. After choosing a target type it presents only the link intents that make sense for that pair, as clear sentences with a live preview and type icons: extend a fact/object type's verbalisation with the role, add the role in a separate expression (generalisation), classify a type, relate concepts (uses / used by / related / subtype / supertype), contain members, or specialise a label by its datatype. Classification links no longer appear as ordinary fact roles and no longer widen a fact type, and model-quality checks now flag meta-level mistakes.