Block Attribute Manager window (BATTMAN / ATTMAN)

BATTMAN and ATTMAN open a manager for the attribute definitions of one
attributed block: block chips with reference counts and a pick button,
a table whose columns are chosen with chips, move up/down, remove, and
an edit card (Attribute / Text / Properties) for the selected row. Apply,
OK and Sync write the list back to the block definition and, when asked,
rebuild the existing references keeping values through tag renames;
each is one undo step. Live changes are taken back on Cancel. Automation
gains attman_dialog.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/app/update/mod.rs

@@ -232,6 +232,7 @@ impl OpenCADStudio {
             }
             Some(GeometricTolerance) => self.geometric_tolerance = None,
             Some(BlockDefinition) => self.block_definition = None,
+            Some(AttMan) => self.attman = None,
             Some(BlockEditPicker) => self.block_edit_picker = None,
             Some(BlockSaveAs) => self.block_save_as = None,
             Some(PdfAttach) => self.pdf_attach = None,
@@ -2407,6 +2408,7 @@ impl OpenCADStudio {
 
             Message::PdfDialog(message) => self.update_pdf_dialog(message),
             Message::AttdefDialog(message) => self.on_attdef_dialog(message),
+            Message::AttMan(message) => self.on_attman(message),
             Message::FieldDialog(message) => self.on_field_dialog(message),
             Message::RefEditDialog(message) => self.update_refedit_dialog(message),
             Message::PcManager(message) => self.update_pc_manager(message),
@@ -9571,6 +9573,13 @@ impl OpenCADStudio {
                     self.close_field_dialog();
                     return Task::none();
                 }
+                // Closing the attribute manager is its Cancel: live changes
+                // are taken back.
+                if self.active_modal == Some(super::ModalKind::AttMan) {
+                    return self.on_attman(
+                        crate::ui::window::attman_dialog::AttManMsg::Cancel,
+                    );
+                }
                 if matches!(
                     self.active_modal,
                     Some(super::ModalKind::AttDef | super::ModalKind::AttDefEdit)