Lessons tab replaces the map tab: chapter > island > lesson list with the island quiz beside it

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/nav/Navigator.tsx

@@ -53,7 +53,7 @@ export function NavigatorProvider({ initial, children }: { initial: Route; child
     const root = stack[0].name;
     return {
       route: stack[stack.length - 1],
-      tab: ['home', 'map', 'ask', 'subscription', 'profile'].includes(root) ? (root as TabName) : null,
+      tab: ['home', 'lessons', 'ask', 'subscription', 'profile'].includes(root) ? (root as TabName) : null,
       canGoBack: stack.length > 1,
       push,
       replace,