chore: 初始化脚手架 — sunny_mochi 企业级 Flutter 模板

Core 基础设施：Flavor 三包体系、Drift+SQLCipher 加密数据库
7 拦截器 Dio 网络栈、CrashReporter 崩溃日志、Sealed Failure 错误体系
5 色板主题系统、Auth 认证骨架（Clean Architecture）、Dev Panel、Mock Adapter

通过验证：flutter analyze（0 errors）、flutter test（全绿）、staging APK 74.8MB

lib/features/auth/presentation/pages/login_page.dart

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+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:sunny_mochi/core/utils/validator.dart';
+import 'package:sunny_mochi/core/widgets/app_button.dart';
+import 'package:sunny_mochi/core/widgets/app_text_field.dart';
+import 'package:sunny_mochi/core/widgets/app_toast.dart';
+import 'package:sunny_mochi/core/widgets/count_down_button.dart';
+import 'package:sunny_mochi/features/auth/presentation/notifiers/auth_notifier.dart';
+
+/// 通用登录页骨架 — 手机号 + 双模式（短信验证码 / 密码）。
+///
+/// TODO: 替换为项目品牌 UI（logo / 背景 / 色彩）。
+class LoginPage extends ConsumerStatefulWidget {
+  const LoginPage({super.key});
+
+  @override
+  ConsumerState<LoginPage> createState() => _LoginPageState();
+}
+
+class _LoginPageState extends ConsumerState<LoginPage>
+    with SingleTickerProviderStateMixin {
+  late final TabController _tabCtrl;
+  final _phoneCtrl = TextEditingController();
+  final _codeCtrl = TextEditingController();
+  final _passwordCtrl = TextEditingController();
+  bool _obscurePassword = true;
+
+  @override
+  void initState() {
+    super.initState();
+    _tabCtrl = TabController(length: 2, vsync: this);
+  }
+
+  @override
+  void dispose() {
+    _tabCtrl.dispose();
+    _phoneCtrl.dispose();
+    _codeCtrl.dispose();
+    _passwordCtrl.dispose();
+    super.dispose();
+  }
+
+  bool get _isSms => _tabCtrl.index == 0;
+
+  Future<void> _onSendCode() async {
+    final phone = _phoneCtrl.text.trim();
+    if (!Validator.isValidPhone(phone)) {
+      if (mounted) {
+        AppToast.show(context, '请输入有效的手机号码', type: ToastType.warning);
+      }
+      return;
+    }
+    try {
+      final echoCode = await ref
+          .read(authProvider.notifier)
+          .sendSmsCode(phone);
+      if (echoCode != null && mounted) {
+        _codeCtrl.text = echoCode; // dev/test 环境自动填入
+      }
+    } on Object catch (e) {
+      if (mounted) {
+        AppToast.show(context, e.toString(), type: ToastType.error);
+      }
+    }
+  }
+
+  Future<void> _onLogin() async {
+    final phone = _phoneCtrl.text.trim();
+    if (!Validator.isValidPhone(phone)) {
+      AppToast.show(context, '请输入有效的手机号码', type: ToastType.warning);
+      return;
+    }
+    if (_isSms) {
+      final code = _codeCtrl.text.trim();
+      if (code.isEmpty) {
+        AppToast.show(context, '请输入验证码', type: ToastType.warning);
+        return;
+      }
+      await ref.read(authProvider.notifier).loginWithPhone(phone, code);
+    } else {
+      final pwd = _passwordCtrl.text;
+      if (pwd.isEmpty) {
+        AppToast.show(context, '请输入密码', type: ToastType.warning);
+        return;
+      }
+      await ref
+          .read(authProvider.notifier)
+          .loginWithPassword(phone, pwd);
+    }
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    final authState = ref.watch(authProvider);
+    final isLoading = authState is AuthLoading;
+
+    ref.listen(authProvider, (_, next) {
+      if (next is AuthError && mounted) {
+        AppToast.show(context, next.message, type: ToastType.error);
+      }
+    });
+
+    return Scaffold(
+      body: SafeArea(
+        child: SingleChildScrollView(
+          padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 40),
+          child: Column(
+            crossAxisAlignment: CrossAxisAlignment.start,
+            children: [
+              const SizedBox(height: 48),
+              // TODO: 替换为项目 Logo
+              const FlutterLogo(size: 64),
+              const SizedBox(height: 32),
+              Text(
+                '欢迎登录',
+                style: Theme.of(context).textTheme.headlineSmall?.copyWith(
+                      fontWeight: FontWeight.bold,
+                    ),
+              ),
+              const SizedBox(height: 32),
+              // 手机号
+              AppTextField(
+                controller: _phoneCtrl,
+                label: '手机号',
+                hint: '请输入手机号',
+                keyboardType: TextInputType.phone,
+                maxLength: 11,
+                prefixIcon: const Icon(Icons.phone_outlined),
+              ),
+              const SizedBox(height: 16),
+              // 模式切换 Tab
+              TabBar(
+                controller: _tabCtrl,
+                onTap: (_) => setState(() {}),
+                tabs: const [
+                  Tab(text: '短信验证码'),
+                  Tab(text: '密码登录'),
+                ],
+              ),
+              const SizedBox(height: 16),
+              // 验证码 / 密码输入
+              if (_isSms)
+                Row(
+                  children: [
+                    Expanded(
+                      child: AppTextField(
+                        controller: _codeCtrl,
+                        label: '验证码',
+                        hint: '请输入验证码',
+                        keyboardType: TextInputType.number,
+                        maxLength: 6,
+                      ),
+                    ),
+                    const SizedBox(width: 12),
+                    CountDownButton(onSend: _onSendCode),
+                  ],
+                )
+              else
+                AppTextField(
+                  controller: _passwordCtrl,
+                  label: '密码',
+                  hint: '请输入密码',
+                  obscureText: _obscurePassword,
+                  suffix: IconButton(
+                    icon: Icon(
+                      _obscurePassword
+                          ? Icons.visibility_outlined
+                          : Icons.visibility_off_outlined,
+                    ),
+                    onPressed: () =>
+                        setState(() => _obscurePassword = !_obscurePassword),
+                  ),
+                ),
+              const SizedBox(height: 32),
+              AppButton(
+                label: '登录',
+                onPressed: _onLogin,
+                loading: isLoading,
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}