Add ringtone selection dropdown and various bugfixes

- Add ComboBox for ringtone selection in Call Settings
- Convert MKV ringtones to WAV format (Linphone only supports WAV)
- Fix ComboSetting to support dialPlan type for international prefix
- Disable account devices feature to prevent API errors
- Disable automatic update check on startup
- Add ringtone fallback to default when custom file not found
- Fix ringtone dropdown to not override setting on initialization

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Linphone/core/App.cpp

@@ -539,7 +539,7 @@ void App::setSelf(QSharedPointer<App>(me)) {
 	                                         });
 	mCoreModelConnection->makeConnectToCore(&App::lForceOidcTimeout, [this] {
 		qDebug() << "App: force oidc timeout";
-		mCoreModelConnection->invokeToModel([this] { emit CoreModel::getInstance()->forceOidcTimeout(); });
+		mCoreModelConnection->invokeToModel([this] { emit CoreModel::getInstance() -> forceOidcTimeout(); });
 	});
 	mCoreModelConnection->makeConnectToModel(&CoreModel::timeoutTimerStarted, [this]() {
 		qDebug() << "App: oidc timer started";

Linphone/core/address-books/carddav/CarddavCore.cpp

@@ -77,7 +77,7 @@ void CarddavCore::setSelf(QSharedPointer<CarddavCore> me) {
 	mCarddavModelConnection = SafeConnection<CarddavCore, CarddavModel>::create(me, mCarddavModel);
 	mCarddavModelConnection->makeConnectToModel(&CarddavModel::saved, [this](bool success, QString message) {
 		mCarddavModelConnection->invokeToCore([this, success, message]() {
-			if (success) emit App::getInstance()->getSettings()->cardDAVAddressBookSynchronized();
+			if (success) emit App::getInstance() -> getSettings()->cardDAVAddressBookSynchronized();
 			emit saved(success, message);
 		});
 	});

Linphone/core/address-books/ldap/LdapCore.cpp

@@ -95,10 +95,10 @@ void LdapCore::setSelf(QSharedPointer<LdapCore> me) {
 	DEFINE_CORE_GETSET_CONNECT(mLdapModelConnection, LdapCore, LdapModel, mLdapModel, bool, debug, Debug)
 
 	mLdapModelConnection->makeConnectToModel(&LdapModel::saved, [this]() {
-		mLdapModelConnection->invokeToCore([this]() { emit App::getInstance()->getSettings()->ldapConfigChanged(); });
+		mLdapModelConnection->invokeToCore([this]() { emit App::getInstance() -> getSettings()->ldapConfigChanged(); });
 	});
 	mLdapModelConnection->makeConnectToModel(&LdapModel::removed, [this]() {
-		mLdapModelConnection->invokeToCore([this]() { emit App::getInstance()->getSettings()->ldapConfigChanged(); });
+		mLdapModelConnection->invokeToCore([this]() { emit App::getInstance() -> getSettings()->ldapConfigChanged(); });
 	});
 }