Plan whole saved-view model deletion from exact visible groups

docs/language.rst

@@ -2279,6 +2279,28 @@ transition row, uses confirmed relation deletion for either key. States and
 referenced Activity/Function definitions remain. Hidden or collapsed rows are
 not keyboard deletion targets.
 
+For a group in a saved architecture or state view, plain Delete retains its
+placement-only Hide meaning; a mixture containing ports, edges or state rows
+MUST refuse Hide rather than silently delete model objects. Explicit group
+model deletion, including focused Shift+Delete, resolves each exact visible
+placement to its semantic element, each port to that port, each stored edge to
+its relation or trace, and each state row to its maintained relation. Navigation
+groupings and inferred edges are not semantic deletion subjects. Every original
+typed member MUST be admitted before redundant semantic subjects or cascade
+commands are reduced. A selected ancestor does not make a hidden or invalid
+member admissible. Existing project validity constraints, including placement
+uniqueness within a diagram, remain in force.
+
+Saved-view aggregate review distinguishes selected visual targets, unique
+semantic subjects, actual deleted records and changed surviving records. Model
+deletion affects all placements of deleted elements in all views. A trace does
+not cause deletion of its counterpart endpoints; an explicitly selected
+counterpart remains an independent deletion subject. Removing a state action
+row deletes its maintained relation, not the referenced Activity or Function.
+The combined candidate and source update MUST form one atomic transaction;
+neither partial primary-only deletion nor intermediate singleton history is
+permitted.
+
 Process and scenario projections have no independent occurrence placements.
 Delete and Shift+Delete request confirmed removal of the selected occurrence,
 participant or maintained link. A link's endpoints and outbound reusable