History: the panel menu has Step Backward, Step Forward and Set History Limit…

The History panel menu held only a disabled History Options… item. The
reference app's History panel menu has Step Backward and Step Forward,
which undo and redo a change, and Set History Limit, which sets the
number of History States.

The panel menu now has Step Backward and Step Forward. They run
edit.undo and edit.redo, and each is disabled when there is no step to
undo or redo, as Edit › Undo and Edit › Redo are. Set History Limit…
opens Preferences at Performance, where History States is set.

Docs: docs/target-app-parity.md.

docs/target-app-parity.md

@@ -457,6 +457,7 @@ Moved from the ROADMAP's "Shipped so far" on 2026-10-10. Update it when a featur
   - Czech render-site labels: desktop/web file filters, diagnostics, suggested preset names and contributor tooltips/plurals now use catalog lookups; gradients have Czech adjective agreement and printer marks have a separate context (PDF/Print and Summary). Search, Home, toolbar/panel tooltips and Preferences already look up their labels. Every complete catalog has rows for these labels and for the Roman and Japanese printer mark styles. Evidence: `i18n::tests::czech_render_site_follow_up`, `i18n::tests::complete_catalogs_translate_render_site_labels`, `dialogs::tests_modal::printer_mark_labels_are_distinct_from_language_names`; see [localization-parity.md](localization-parity.md).
   - Localised UI: menus (in-window and native), panels, dialogs, toolbar and Preferences read from per-language catalogs (`crates/ui-egui/src/i18n`, see `docs/development.md`); Traditional Chinese (Taiwan), Simplified Chinese (mainland), Japanese, Korean, Vietnamese, German, Spanish, French, Italian, Polish, Brazilian Portuguese, Russian and Ukrainian ship complete, and Czech covers every menu label (and more), with system-locale detection on macOS, Windows, Linux and the web (the browser's languages, or `?lang=`), a Language preference and, on macOS, a VectorCraft ▸ Language menu. Names are never translated (fonts and their styles, layers, artboards, saved presets, user libraries, custom workspaces, recent files, plug-ins).
   - The History panel translates the undo step names the engine, the tools and the shell write as literals: each has a row in every complete catalog (`every_undo_label_is_translated`), and a step whose catalog row exists only with an ellipsis (such as an effect's menu name) shows that row without the ellipsis.
+  - The History panel menu has Step Backward and Step Forward, which run Edit › Undo and Edit › Redo and are disabled when there is no step to undo or redo, and Set History Limit…, which opens Preferences at Performance, where History States is set. Not done: Clear History and a new document from the selected state.
   - Native macOS menu bar, vector tool cursors, a ⌘K command palette, middle-button panning with any tool. Native menus explicitly end tracking on command selection, outside window presses and Escape; menu updates wait until tracking ends, and a dismissing press never starts a canvas gesture (M14.8).
   - The errors of the blend spine commands (Move Spine Point, Reshape Spine Segment, Add Spine Point and Delete Spine Point) show in the status bar in the interface language: each has a row in every catalog that translates all status and error messages and in Bulgarian (`blend_spine_param_errors_are_translated`).
   - The macOS menu bar is built from the in-window menus (one model, `native_menu`) and laid out as a Mac app's: the VectorCraft menu holds About, Settings ▸ (each Preferences page, General… ⌘K), Language ▸, Appearance ▸ (UI brightness), Services, Hide VectorCraft ⌃⌘H (⌘H stays Hide Edges), Hide Others, Show All and Quit; Window gains Minimize ⌃⌘M, Zoom and Bring All to Front, and Help the system's search field. Its key equivalents go back to egui as key presses, so user shortcuts, focused text fields and the Type tool's input method behave as in the window, and nothing fires twice; enabled, check marks and labels update in place. `--in-window-menus` or `VECTORCRAFT_IN_WINDOW_MENUS=1` keeps the menus in the window; `ui.inspect` reports `nativeMenuBar`.