fix(layout): focus inline rename field on RENAME

Renaming a layout tab left keyboard focus on the command line, so typed
characters landed there until the user clicked the tab. Give the inline
rename text_input a stable id and return a focus task when the rename
starts so the user types straight into the field. (issue #86)

Co-Authored-By: Claude Opus 4.8 <[email protected]>

src/app/update.rs

@@ -5103,6 +5103,11 @@ impl OpenCADStudio {
                 if name != "Model" {
                     self.layout_rename_state = Some((name.clone(), name));
                     self.layout_context_menu = None;
+                    // Focus the inline field so the user types into it
+                    // directly instead of the command line (issue #86).
+                    return iced::widget::operation::focus(iced::widget::Id::new(
+                        crate::ui::statusbar::LAYOUT_RENAME_INPUT_ID,
+                    ));
                 }
                 Task::none()
             }