fix(eq): seed device ID at startup and add device management UI

Fix multi-device EQ auto-switching by calling obtenerDispositivoActual()
during cargarPersistido() to seed the initial device ID. Add device
management modal with rename support, EQ preset editing, and connection
status indicator. Translate device UI keys to all 13 locales.

lib/l10n/gen/app_localizations_es.dart

@@ -1259,4 +1259,24 @@ class AppLocalizationsEs extends AppLocalizations {
   String advancedEqDevicePresetLabel(Object presetName) {
     return 'Preset: $presetName';
   }
+
+  @override
+  String preNoticeCountdown(int minutes) {
+    return 'Empieza en $minutes min';
+  }
+
+  @override
+  String get eqDeviceEditTitle => 'Editar dispositivo';
+
+  @override
+  String get eqDeviceNameLabel => 'Nombre del dispositivo';
+
+  @override
+  String get eqDeviceNameHint => 'Ej: Altavoz del living';
+
+  @override
+  String get eqDeviceNameConfirm => 'Guardar';
+
+  @override
+  String get eqDeviceConnected => 'Conectado';
 }