feat: Add authentication redirects for / and /chat routes

Implemented server-side authentication redirects:
- Root (/) redirects to /chat if authenticated, /login if not
- /chat route requires authentication via layout component
- Removed deprecated middleware file in favor of Next.js server components

This ensures users are properly directed based on their authentication state.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

app/chat/layout.tsx

@@ -0,0 +1,21 @@
+import { redirect } from 'next/navigation';
+import { cookies } from 'next/headers';
+
+/**
+ * Chat route layout - ensures user is authenticated before showing chat
+ */
+export default async function ChatLayout({
+  children,
+}: {
+  children: React.ReactNode;
+}) {
+  const cookieStore = await cookies();
+  const authCookie = cookieStore.get('ponderants-auth');
+
+  // Redirect to login if not authenticated
+  if (!authCookie) {
+    redirect('/login');
+  }
+
+  return <>{children}</>;
+}

app/chat/page.tsx

@@ -12,12 +12,10 @@ import {
   Group,
   Text,
 } from '@mantine/core';
-import { useRouter } from 'next/navigation';
-import { useEffect, useRef, useState } from 'react';
+import { useRef, useState, useEffect } from 'react';
 import { MicrophoneRecorder } from '@/components/MicrophoneRecorder';
 
 export default function ChatPage() {
-  const router = useRouter();
   const viewport = useRef<HTMLDivElement>(null);
   const [input, setInput] = useState('');
 

app/page.tsx

@@ -1,14 +1,16 @@
-import { Stack, Title, Paper, Button, Center } from '@mantine/core';
+import { redirect } from 'next/navigation';
+import { cookies } from 'next/headers';
 
-export default function Home() {
-  return (
-    <Center h="100vh">
-      <Paper w={400} p="xl">
-        <Stack align="center">
-          <Title order={1}>Ponderants</Title>
-          <Button>Test Button</Button>
-        </Stack>
-      </Paper>
-    </Center>
-  );
+/**
+ * Root page - redirects to /chat if authenticated, /login if not
+ */
+export default async function Home() {
+  const cookieStore = await cookies();
+  const authCookie = cookieStore.get('ponderants-auth');
+
+  if (authCookie) {
+    redirect('/chat');
+  } else {
+    redirect('/login');
+  }
 }