Portrait tablet and tablet settings layouts (#188)

Co-authored-by: orchestrator-agent <20+orchestrator-agent@code.cubecraftcreations.com>

web/src/shell/useBreakpoint.ts

@@ -7,6 +7,12 @@ export type Breakpoint = 'mobile' | 'tablet' | 'desktop'
 export const TABLET_QUERY = '(min-width: 768px)'
 export const DESKTOP_QUERY = '(min-width: 1200px)'
 
+export type Orientation = 'portrait' | 'landscape'
+
+// A tablet held upright (820 × 1180) has the rail and the tablet layout but
+// far less width than one on its side, so pages reflow for it.
+export const PORTRAIT_QUERY = '(orientation: portrait)'
+
 // The layout the current viewport calls for, updated as the viewport crosses
 // a breakpoint.
 export function useBreakpoint(): Breakpoint {
@@ -29,3 +35,16 @@ export function useBreakpoint(): Breakpoint {
     lists.desktop.matches ? 'desktop' : lists.tablet.matches ? 'tablet' : 'mobile',
   )
 }
+
+// The viewport's orientation, updated as the device turns.
+export function useOrientation(): Orientation {
+  const [list] = useState(() => window.matchMedia(PORTRAIT_QUERY))
+  const subscribe = useCallback(
+    (onChange: () => void) => {
+      list.addEventListener('change', onChange)
+      return () => list.removeEventListener('change', onChange)
+    },
+    [list],
+  )
+  return useSyncExternalStore(subscribe, () => (list.matches ? 'portrait' : 'landscape'))
+}