feat(alarmas): surface scheduling failures on the alarm card

Wires EstadoAlarmas.ultimaExcepcionPara into PantallaAlarmas: an
alarm with an outstanding scheduling-failure exception now shows a
calm warning line (distinguishing a pre-notice-only failure from the
alarm itself not being registered) with a tap target into the
reliability diagnostics screen. The warning is its own small tap
target nested inside the existing card InkWell, so tap-to-edit,
swipe-to-delete and the hero "Saltar" chip are untouched.

Adds alarmCardSchedulingFailedMessage/alarmCardPreNoticeFailedMessage
to all 13 ARB locales with real per-language translations (verified
against arb_parity_test and arb_anti_copy_test).

lib/l10n/app_zh.arb

@@ -842,6 +842,8 @@
     }
   },
   "alarmCardVacationPausedBadge": "因假期已暂停",
+  "alarmCardSchedulingFailedMessage": "该闹钟未能在系统中注册，因此可能不会响铃。",
+  "alarmCardPreNoticeFailedMessage": "该闹钟已设置，但其提前提醒未能设置成功。",
   "alarmDiagnosticsExactAlarmsTitle": "精确闹钟排程",
   "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。",
   "alarmDiagnosticsNotificationsTitle": "通知",