feat: add a compact icon-only top navigation toggle (#1363)

* feat: add a compact icon-only top navigation toggle

Add a browser-local "Top navigation labels" preference under Settings >
Appearance. With it off, the desktop top navigation renders icon-only;
each destination keeps an aria-label, gains a hover/focus tooltip, and
stays reachable from the command palette. The setting defaults on, so
current behavior is preserved, and the mobile navigation always keeps
its labels.

Also left-align the desktop nav (previously centered) and shorten the
longest nav label from "Auto-Update" to "Update" so the bar scans faster.

* feat: let the icon-only top nav be left or centered

Add a "Top navigation alignment" preference under Settings > Appearance
that appears only when top navigation labels are off. It places the
icon-only bar against the left edge (the default) or centered. With
labels on, the nav always stays left so the longer labels read from the
edge. The choice is browser-local and persists per device.

frontend/src/components/EditorLayout.tsx

@@ -38,6 +38,8 @@ import { useNextAutoUpdateRun } from '@/components/sidebar/useNextAutoUpdateRun'
 import { usePanelSessionStartedAt } from '@/components/sidebar/usePanelSessionStartedAt';
 import type { SidebarActivityAction } from '@/components/sidebar/SidebarActivityTicker';
 import { useComposeDiffPreviewEnabled } from '@/hooks/use-compose-diff-preview-enabled';
+import { useTopNavLabels } from '@/hooks/use-top-nav-labels';
+import { useTopNavAlign } from '@/hooks/use-top-nav-align';
 import { toast } from '@/components/ui/toast-store';
 import { useIsMobile } from '@/hooks/use-is-mobile';
 import { MobileTabBar } from './MobileTabBar';
@@ -144,6 +146,8 @@ export default function EditorLayout() {
   }, [setCreateDialogOpen]);
 
   const [diffPreviewEnabled] = useComposeDiffPreviewEnabled();
+  const [topNavLabels] = useTopNavLabels();
+  const [topNavAlign] = useTopNavAlign();
 
   // Use a ref to break the circular dependency:
   // useViewNavigationState needs onNavigateToDashboard -> resetEditorState
@@ -665,6 +669,8 @@ export default function EditorLayout() {
           themeSwitch={themeSwitchEl}
           notifications={notificationsEl}
           userMenu={userMenuEl}
+          showLabels={topNavLabels}
+          navAlign={topNavAlign}
         />
       );