feat(routing): 域名级系统锁冲突提示 + 重置默认按钮 + 客户端 follow-up 清理

承接 FT-A(GET /v1/me/routing 含只读 system_locked_domains)。

- RoutingProfile 加只读 systemLockedDomains(fromJson 读/toJson 不输出);
  routing_screen 冲突检测扩展到域名类规则(domain/domain_suffix/domain_keyword
  命中锁定域名 → systemLocked),ip_cidr 私网启发式保留。
- RoutingProfile.defaults() + RoutingProfileNotifier.resetToDefault()(复用
  _persist:乐观更新/失败回滚/存成功后自动重连,保留只读 systemLockedDomains
  不丢)+ routing_screen 加「重置默认」按钮与二次确认弹层(新增 3 个 l10n 键)。
- RoutingRule.copyWith 用哨兵支持 note 显式清空为 null;RoutingRule/Builtin/
  RoutingProfile 加值相等 operator==/hashCode。
- T8 smartRouteSub 清理:grep 全仓发现 design/prototype/i18n/alias.json →
  gen_proto_i18n.mjs(CI 漂移闸)仍有活引用,按计划口径不删,详见
  .superpowers/sdd/task-FTB-report.md。

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/test/unit/routing_profile_model_test.dart

@@ -36,4 +36,67 @@ void main() {
     expect(p.builtin.lanDirect, isTrue);
     expect(p.builtin.privateViaTunnel, isTrue);
   });
+
+  test('systemLockedDomains:fromJson 读取,默认空,toJson 不输出(只读字段)', () {
+    final withLocks = RoutingProfile.fromJson({
+      'mode': 'rule',
+      'rules': [],
+      'final': 'proxy',
+      'system_locked_domains': ['git.yanmeiai.com', 'admin.yanmeiai.com'],
+    });
+    expect(withLocks.systemLockedDomains, ['git.yanmeiai.com', 'admin.yanmeiai.com']);
+    expect(withLocks.toJson().containsKey('system_locked_domains'), isFalse);
+
+    final withoutLocks = RoutingProfile.fromJson({'mode': 'rule', 'rules': [], 'final': 'proxy'});
+    expect(withoutLocks.systemLockedDomains, isEmpty);
+  });
+
+  test('RoutingProfile.defaults() 对齐服务端 routing.Default()', () {
+    final d = RoutingProfile.defaults();
+    expect(d.mode, 'rule');
+    expect(d.builtin.chinaDirect, isTrue);
+    expect(d.builtin.lanDirect, isTrue);
+    expect(d.builtin.privateViaTunnel, isTrue);
+    expect(d.rules, isEmpty);
+    expect(d.finalAction, 'proxy');
+  });
+
+  test('RoutingRule.copyWith 用哨兵让 note 可清空为 null', () {
+    const r = RoutingRule(type: 'domain', value: 'a.com', action: 'proxy', note: 'ci');
+    final cleared = r.copyWith(note: null);
+    expect(cleared.note, isNull, reason: '显式传 null 应清空 note,而不是被 ?? 吞掉');
+
+    final unchanged = r.copyWith(value: 'b.com');
+    expect(unchanged.note, 'ci', reason: '不传 note 时应保留原值');
+  });
+
+  test('RoutingRule / Builtin / RoutingProfile 值相等(operator==)', () {
+    const r1 = RoutingRule(type: 'domain', value: 'a.com', action: 'proxy', note: 'x');
+    const r2 = RoutingRule(type: 'domain', value: 'a.com', action: 'proxy', note: 'x');
+    const r3 = RoutingRule(type: 'domain', value: 'a.com', action: 'direct', note: 'x');
+    expect(r1, r2);
+    expect(r1.hashCode, r2.hashCode);
+    expect(r1 == r3, isFalse);
+
+    const b1 = Builtin(chinaDirect: true, lanDirect: false, privateViaTunnel: true);
+    const b2 = Builtin(chinaDirect: true, lanDirect: false, privateViaTunnel: true);
+    const b3 = Builtin();
+    expect(b1, b2);
+    expect(b1.hashCode, b2.hashCode);
+    expect(b1 == b3, isFalse);
+
+    const p1 = RoutingProfile(mode: 'rule', rules: [r1], finalAction: 'proxy');
+    const p2 = RoutingProfile(mode: 'rule', rules: [r2], finalAction: 'proxy');
+    final p3 = RoutingProfile.fromJson({
+      'mode': 'rule',
+      'rules': [
+        {'type': 'domain', 'value': 'a.com', 'action': 'proxy', 'note': 'x', 'enabled': true}
+      ],
+      'final': 'proxy',
+      'system_locked_domains': ['git.yanmeiai.com'],
+    });
+    expect(p1, p2);
+    expect(p1.hashCode, p2.hashCode);
+    expect(p1 == p3, isFalse, reason: 'systemLockedDomains 不同应视为不相等');
+  });
 }