Egui::TitleBarTabs::TabPart

The StyledPart behind every card (tab, its X, the "+" button — see widgets/styled_part.cr): the strip paints in place, so the part carries the inspector meta AND declares the title_bar.tab class keys the strip reads. Class rules and per-element inspector overrides resolve per card id (title_bar_tabs/tab/…), so both «Класс» and «Элемент» tabs edit the strip live. Geometry keys (min_width/pad_x/font_size/top_gap) re-run the measure below — the class-level edit reflows every card, an element edit one.