feat(alarmas): replace one-line reliability button with full diagnostics screen

Surface all six DiagnosticoAlarmasAndroid fields instead of three: the
battery-optimization exemption and native pending-alarm count were
already collected but silently dropped by the old widget. Each failing
signal now offers a "Fix this" action that opens the right system
settings screen (exact alarms, notifications, full-screen intent,
battery optimization), guarded by SDK level and never crashing when a
ROM lacks that screen. Manufacturers known for aggressive background
killing (Xiaomi/Redmi/POCO, Huawei, Oppo, Vivo, OnePlus, Samsung) get
an honest explanation that Autostart must be enabled manually, since
there is no API to detect or grant it.

Notifications now deep-links straight to
ACTION_APP_NOTIFICATION_SETTINGS via a new openNotificationSettings
native method, instead of reusing the runtime permission popup meant
for first-time alarm creation.

New copy is added to all 13 ARB locales with real per-language
translations (not Spanish copies), verified by the ARB parity and
anti-copy tests plus the corruption scanner.

lib/l10n/gen/app_localizations_zh.dart

@@ -1637,4 +1637,66 @@ class AppLocalizationsZh extends AppLocalizations {
 
   @override
   String get alarmCardVacationPausedBadge => '因假期已暂停';
+
+  @override
+  String get alarmDiagnosticsExactAlarmsTitle => '精确闹钟排程';
+
+  @override
+  String get alarmDiagnosticsExactAlarmsHint => '即使手机处于休眠状态，也能让闹钟在设定的准确时间响起。';
+
+  @override
+  String get alarmDiagnosticsNotificationsTitle => '通知';
+
+  @override
+  String get alarmDiagnosticsNotificationsHint => '显示闹钟和提前提醒需要用到。';
+
+  @override
+  String get alarmDiagnosticsFullScreenTitle => '闹钟全屏显示';
+
+  @override
+  String get alarmDiagnosticsFullScreenHint => '即使手机已锁屏，也能让响铃界面自动出现。';
+
+  @override
+  String get alarmDiagnosticsBatteryTitle => '电池优化';
+
+  @override
+  String get alarmDiagnosticsBatteryHint => '防止系统在后台关闭PluriWave，让闹钟仍然可以响起。';
+
+  @override
+  String get alarmDiagnosticsNativeCountTitle => '已在Android系统注册的闹钟';
+
+  @override
+  String alarmDiagnosticsNativeCountValue(int count) {
+    return '当前已注册：$count';
+  }
+
+  @override
+  String get alarmDiagnosticsNativeCountAttentionHint =>
+      '你已开启一个闹钟，但目前还没有闹钟在系统中注册。请重新打开PluriWave，或先解决上面列出的问题。';
+
+  @override
+  String get alarmDiagnosticsManufacturerLabel => '制造商';
+
+  @override
+  String get alarmDiagnosticsSdkLabel => 'Android版本（SDK）';
+
+  @override
+  String get alarmDiagnosticsNeedsAttentionStatus => '需要注意';
+
+  @override
+  String get alarmDiagnosticsAutostartTitle => '此手机还需要一步手动设置';
+
+  @override
+  String alarmDiagnosticsAutostartBody(String manufacturer) {
+    return '$manufacturer手机经常会关闭后台运行的应用以节省电量。没有任何设置可以让PluriWave自行开启——你需要自己为PluriWave开启自启动（有时也叫\"Autostart\"或\"后台活动\"）。请在设置中查找应用或电池选项，或者查看手机自带的安全应用。';
+  }
+
+  @override
+  String get alarmDiagnosticsFixAction => '解决';
+
+  @override
+  String get alarmDiagnosticsIntentUnavailable => '无法在此手机上打开该设置界面。请尝试在设置中手动查找。';
+
+  @override
+  String get alarmDiagnosticsUnavailableHint => '我们还无法检查你的闹钟设置。';
 }