fix iOS language picker style in dark mode (#6804)

Co-authored-by: skipness <ckhf@proton.me>

src/components/AppLanguageDropdown.tsx

@@ -34,6 +34,7 @@ export function AppLanguageDropdown(_props: ViewStyleProp) {
   return (
     <View style={a.relative}>
       <RNPickerSelect
+        darkTheme={t.scheme === 'dark'}
         placeholder={{}}
         value={sanitizedLang}
         onValueChange={onChangeAppLanguage}

src/screens/Settings/LanguageSettings.tsx

@@ -80,6 +80,7 @@ export function LanguageSettingsScreen({}: Props) {
               </Text>
               <View style={[a.relative, web([a.w_full, {maxWidth: 400}])]}>
                 <RNPickerSelect
+                  darkTheme={t.scheme === 'dark'}
                   placeholder={{}}
                   value={sanitizeAppLanguageSetting(langPrefs.appLanguage)}
                   onValueChange={onChangeAppLanguage}
@@ -165,6 +166,7 @@ export function LanguageSettingsScreen({}: Props) {
               </Text>
               <View style={[a.relative, web([a.w_full, {maxWidth: 400}])]}>
                 <RNPickerSelect
+                  darkTheme={t.scheme === 'dark'}
                   placeholder={{}}
                   value={langPrefs.primaryLanguage}
                   onValueChange={onChangePrimaryLanguage}

src/view/screens/Search/Search.tsx

@@ -394,6 +394,7 @@ function SearchLanguageDropdown({
 
   return (
     <RNPickerSelect
+      darkTheme={t.scheme === 'dark'}
       placeholder={{}}
       value={value}
       onValueChange={onChange}