Phase 3 completed: Flutter MVP with live streaming and auto-refresh

frontend/lib/pages/login_page.dart

@@ -0,0 +1,66 @@
+import 'dart:convert';
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+import '../providers/auth_provider.dart';
+import '../providers/settings_provider.dart';
+import '../services/api_service.dart';
+import 'register_page.dart';
+
+class LoginPage extends StatefulWidget {
+  @override
+  _LoginPageState createState() => _LoginPageState();
+}
+
+class _LoginPageState extends State<LoginPage> {
+  final _usernameController = TextEditingController();
+  final _passwordController = TextEditingController();
+  bool _isLoading = false;
+
+  void _handleLogin() async {
+    setState(() => _isLoading = true);
+    final settings = context.read<SettingsProvider>();
+    final auth = context.read<AuthProvider>();
+    final api = ApiService(settings, null);
+
+    try {
+      final response = await api.login(
+        _usernameController.text,
+        _passwordController.text,
+      );
+
+      if (response.statusCode == 200) {
+        final data = jsonDecode(response.body);
+        await auth.login(data['token']);
+      } else {
+        final error = jsonDecode(response.body)['error'] ?? "Login Failed";
+        ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text(error)));
+      }
+    } catch (e) {
+      ScaffoldMessenger.of(context).showSnackBar(SnackBar(content: Text("Network Error")));
+    } finally {
+      setState(() => _isLoading = false);
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: Text("Login")),
+      body: Padding(
+        padding: const EdgeInsets.all(16.0),
+        child: Column(
+          children: [
+            TextField(controller: _usernameController, decoration: InputDecoration(labelText: "Username")),
+            TextField(controller: _passwordController, decoration: InputDecoration(labelText: "Password"), obscureText: true),
+            SizedBox(height: 20),
+            _isLoading ? CircularProgressIndicator() : ElevatedButton(onPressed: _handleLogin, child: Text("Login")),
+            TextButton(
+              onPressed: () => Navigator.push(context, MaterialPageRoute(builder: (_) => RegisterPage())),
+              child: Text("Don't have an account? Register"),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}