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 <noreply@anthropic.com>

src/app/mod.rs

@@ -585,6 +585,8 @@ pub(super) struct OpenCADStudio {
     /// ATTDEF dialog and Edit Attribute Definition dialog; `None` while closed.
     attdef_dialog: Option<crate::ui::window::attdef_dialog::AttdefDialogState>,
     attdef_edit: Option<crate::ui::window::attdef_dialog::AttdefEditState>,
+    /// Block Attribute Manager working copy; `None` while it is closed.
+    attman: Option<crate::ui::window::attman_dialog::AttManState>,
     /// Field dialog working copy; `None` while closed.
     field_dialog: Option<crate::ui::window::field_dialog::FieldDialogState>,
     point_cloud_color_map: Option<crate::ui::window::pdf_dialogs::PointCloudColorMapState>,
@@ -2184,6 +2186,8 @@ pub enum ModalKind {
     GeometricTolerance,
     AttDef,
     AttDefEdit,
+    /// Block Attribute Manager (BATTMAN / ATTMAN).
+    AttMan,
     CountInvalidArea,
     Field,
     DraftingSettings,
@@ -4395,6 +4399,8 @@ pub enum Message {
     /// An edit in one of the PDF dialogs.
     PdfDialog(crate::ui::window::pdf_dialogs::PdfDialogMsg),
     AttdefDialog(crate::ui::window::attdef_dialog::AttdefDialogMsg),
+    /// Block Attribute Manager edits.
+    AttMan(crate::ui::window::attman_dialog::AttManMsg),
     FieldDialog(crate::ui::window::field_dialog::FieldDialogMsg),
     /// An edit in the Edit Reference dialog.
     RefEditDialog(crate::ui::window::refedit_dialog::RefEditDialogMsg),
@@ -4607,6 +4613,7 @@ impl OpenCADStudio {
             pdf_attach: None,
             point_cloud_attach: None,
             attdef_dialog: None,
+            attman: None,
             attdef_edit: None,
             field_dialog: None,
             point_cloud_color_map: None,