feat: add token-saver dashboard page

- extract token saver into its own route /dashboard/token-saver
- slim down EndpointPageClient
- add token-saver nav to Header and Sidebar

Co-authored-by: Cursor <cursoragent@cursor.com>

src/shared/components/Sidebar.js

@@ -24,7 +24,7 @@ const navItems = [
   { href: "/dashboard/combos", label: "Combos", icon: "layers" },
   { href: "/dashboard/usage", label: "Usage", icon: "bar_chart" },
   { href: "/dashboard/quota", label: "Quota Tracker", icon: "data_usage" },
-  { href: "/dashboard/mitm", label: "MITM", icon: "security" },
+  { href: "/dashboard/token-saver", label: "Token Saver", icon: "savings" },
   { href: "/dashboard/cli-tools", label: "CLI Tools", icon: "terminal" },
 ];