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_en.dart

@@ -1250,4 +1250,24 @@ class AppLocalizationsEn extends AppLocalizations {
   String advancedEqDevicePresetLabel(Object presetName) {
     return 'Preset: $presetName';
   }
+
+  @override
+  String preNoticeCountdown(int minutes) {
+    return 'Starts in $minutes min';
+  }
+
+  @override
+  String get eqDeviceEditTitle => 'Edit device';
+
+  @override
+  String get eqDeviceNameLabel => 'Device name';
+
+  @override
+  String get eqDeviceNameHint => 'e.g. Living Room Speaker';
+
+  @override
+  String get eqDeviceNameConfirm => 'Save';
+
+  @override
+  String get eqDeviceConnected => 'Connected';
 }