Fix redundant loop calling ConnectionsManager.setLangCode in LocaleController - #2032

Summary

In LocaleController.applyRemoteLanguage(), ConnectionsManager.setLangCode(localeInfo.getLangCode()) was being called inside a for (int a = 0; a < UserConfig.MAX_ACCOUNT_COUNT; a++) loop.

However, ConnectionsManager.setLangCode() is a static method that already iterates over all accounts internally (0..UserConfig.MAX_ACCOUNT_COUNT) and invokes native_setLangCode(a, langCode) for each account:

public static void setLangCode(String langCode) {
    langCode = langCode.replace('_', '-').toLowerCase();
    for (int a = 0; a < UserConfig.MAX_ACCOUNT_COUNT; a++) {
        native_setLangCode(a, langCode);
    }
}

Because of this outer loop in LocaleController, native_setLangCode was being called MAX_ACCOUNT_COUNT * MAX_ACCOUNT_COUNT times (16 calls when MAX_ACCOUNT_COUNT = 4), triggering redundant JNI string allocations and scheduling redundant native tasks to each account 4 times instead of once.

Changes

Remove the redundant outer for loop in LocaleController.applyRemoteLanguage(), aligning with the single invocation pattern used in LocaleController.applyLanguage().