Specify focused removal semantics and document diagram shortcuts

crates/oa-desktop/src/guide.rs

@@ -310,7 +310,7 @@ fn article(topic: Topic) -> Article {
                                 "Choose Containment for semantic children, Architecture · allocated work for responsibilities, Functional dataflow for work and exchanges, or Missions & capabilities for outcomes. All relationships is a broader exploration view; OA ↔ SA traceability displays counterparts.",
                                 "Select an element and edit Semantic parent to change ownership. Use an Allocation relationship to change responsibility. Apply changes validates the semantic change.",
                                 "Scroll to zoom and use Fit to frame the current view. In allocated-work views, dragging work changes its assignment and placement together. Choose Arrange next drag or press Alt+A to move work without changing responsibility for that one drag; Escape cancels the armed action. Auto-layout arranges the whole view. Export SVG produces a shareable view.",
-                                "Select a diagram node to access Placement, Fold / unfold and Hide. Hide removes its view placement; Delete from model removes model records and requires review of the affected references.",
+                                "Select a diagram node to access Placement, Fold / unfold and Hide. With the canvas focused, Delete hides its placement; Shift+Delete asks to remove the model element. Other views retain a hidden element. Undo restores either change.",
                             ],
                         ),
                         explain(
@@ -570,7 +570,7 @@ fn article(topic: Topic) -> Article {
                         ),
                         explain(
                             "Navigate and recover a view",
-                            "Middle-button drag pans; scroll or use −/+ to zoom, and Fit frames the diagram. Right-click a container for Fold contents or Unfold contents, or choose Placement properties for exact coordinates and size. Hide from this diagram removes only its placement; Show an element not yet in this view restores missing elements. Escape cancels a drawing gesture. Undo restores each completed gesture or menu edit, and Model checks identifies unfinished structures.",
+                            "Middle-button drag pans; scroll or use −/+ to zoom, and Fit frames the diagram. Right-click a container for Fold contents or Unfold contents, or choose Placement properties for exact coordinates and size. With the canvas focused, Delete hides a selected state placement; Shift+Delete confirms model removal. Delete on an action or internal-transition row confirms removal of that relation, preserving its states and referenced work. Escape cancels a drawing gesture. Undo restores each completed edit, and Model checks identifies unfinished structures.",
                         ),
                         explain(
                             "One saved diagram across editors",
@@ -978,6 +978,10 @@ fn article(topic: Topic) -> Article {
                             "Shortcuts act on the current project. In Textual model, undo and redo affect the source draft.",
                             "Ctrl+N          New project\nCtrl+O          Open model\nCtrl+S          Save all\nCtrl+Shift+S    Save as\nCtrl+Z          Undo\nCtrl+Shift+Z    Redo\nCtrl+Y          Redo\nEscape          Cancel the active dialog",
                         ),
+                        explain(
+                            "Remove a diagram item",
+                            "Click the diagram to give it keyboard focus. Delete hides an architecture or state placement; Shift+Delete asks to remove its model element. A selected route bend is removed first. Process and scenario items, links, and state action rows use confirmation for either key because they have no separate placement. Removing an occurrence preserves its reusable definition. Removing a scenario participant retains its messages with affected participant references cleared; removing a fragment also removes its owned branches and steps. Read the captured target and effect before confirming. Escape cancels, and Undo restores the complete change. Inside an expanded reusable process, open its definition to edit its contents, or select the outer reference to remove that use. Text fields keep their normal Delete behavior.",
+                        ),
                         walkthrough(
                             "Save and share a model",
                             &[