feat: add protected role dashboard placeholders

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01AWxyMibCuGGtSQSqfajDQ7

app/(protected)/layout.tsx

@@ -0,0 +1,18 @@
+// app/(protected)/layout.tsx
+import { createClient } from '@/lib/supabase/server'
+import { redirect } from 'next/navigation'
+
+export default async function ProtectedLayout({
+  children,
+}: {
+  children: React.ReactNode
+}) {
+  const supabase = await createClient()
+  const {
+    data: { user },
+  } = await supabase.auth.getUser()
+
+  if (!user) redirect('/login')
+
+  return <>{children}</>
+}