Add option to override user profile settings for audio & subtitle languages (#1680)

## Description
Adds settings under the "User profile settings" section which allows for
specifying preferred languages for audio and subtitles and the preferred
subtitle mode.

By default (matching existing Wholphin behavior), the preferred
languages and subtitle mode are derived from the user's profile settings
provided by the server which can be set on the WebUI:
User->Settings->Playback or Subtitles. However, this isn't well
understood and Wholphin doesn't display these values anywhere, so many
users were confused.

The preferred languages and subtitle mode can now be configured from
within Wholphin. Setting these will **not** update the server. The
settings are **only** used locally.

### Related issues
Related to #319
Closes #790

### Testing
Emulator manually changing some settings, added additional unit tests to
ensure the overrides are respected when choosing tracks

## Screenshots
### Settings page
<img width="1280" height="720" alt="settings_01 Large"
src="https://github.com/user-attachments/assets/28cc2f6b-3a60-42a4-b268-48695086d566"
/>

### Clicking into "More user profile settings"
<img width="1280" height="720" alt="settings_02 Large"
src="https://github.com/user-attachments/assets/6c3be3aa-c177-4d44-8060-b76d15fb10d7"
/>

### Language choice dialog

Can filter languages by typing in the search box at the top

<img width="1280" height="720" alt="settings_03 Large"
src="https://github.com/user-attachments/assets/c014d0ba-8d5b-4201-a6ee-4876b478148c"
/>


## AI or LLM usage
None

app/src/main/java/com/github/damontecres/wholphin/services/StreamChoiceService.kt

@@ -5,7 +5,9 @@ import com.github.damontecres.wholphin.data.ServerRepository
 import com.github.damontecres.wholphin.data.model.ItemPlayback
 import com.github.damontecres.wholphin.data.model.PlaybackLanguageChoice
 import com.github.damontecres.wholphin.data.model.TrackIndex
+import com.github.damontecres.wholphin.preferences.SubtitleModePreference
 import com.github.damontecres.wholphin.preferences.UserPreferences
+import com.github.damontecres.wholphin.preferences.UserProfileSettings
 import com.github.damontecres.wholphin.ui.isNotNullOrBlank
 import com.github.damontecres.wholphin.ui.letNotEmpty
 import org.jellyfin.sdk.model.api.BaseItemDto
@@ -135,7 +137,17 @@ class StreamChoiceService
                 val seriesLang =
                     playbackLanguageChoice?.audioLanguage?.takeIf { it.isNotNullOrBlank() }
                 // If the user has chosen a different language for the series, prefer that
-                val audioLanguage = seriesLang ?: userConfig?.audioLanguagePreference
+                val audioLanguage =
+                    if (seriesLang != null) {
+                        seriesLang
+                    } else {
+                        val pref = prefs.userPreferences?.preferredAudioLanguage
+                        when (pref) {
+                            UserProfileSettings.USE_USER_PROFILE -> userConfig?.audioLanguagePreference
+                            UserProfileSettings.PREFER_ANY_LANGUAGE -> null
+                            else -> pref
+                        }
+                    }
 
                 if (audioLanguage.isNotNullOrBlank()) {
                     val sorted =
@@ -226,23 +238,26 @@ class StreamChoiceService
         ): MediaStream? {
             if (itemPlayback?.subtitleIndex == TrackIndex.DISABLED) {
                 return null
-            } else if (itemPlayback?.subtitleIndex == TrackIndex.ONLY_FORCED) {
+            }
+            val seriesLang =
+                playbackLanguageChoice?.subtitleLanguage?.takeIf { it.isNotNullOrBlank() }
+            val subtitleLanguage =
+                if (seriesLang != null) {
+                    seriesLang
+                } else {
+                    val pref = prefs.userPreferences?.preferredSubtitleLanguage
+                    when (pref) {
+                        UserProfileSettings.USE_USER_PROFILE -> userConfig?.subtitleLanguagePreference
+                        UserProfileSettings.PREFER_ANY_LANGUAGE -> null
+                        else -> pref
+                    }?.takeIf { it.isNotNullOrBlank() }
+                }
+            if (itemPlayback?.subtitleIndex == TrackIndex.ONLY_FORCED) {
                 // Client-side manual override: User selected "Only Forced" in player menu
-                val seriesLang =
-                    playbackLanguageChoice?.subtitleLanguage?.takeIf { it.isNotNullOrBlank() }
-                val subtitleLanguage =
-                    (seriesLang ?: userConfig?.subtitleLanguagePreference)
-                        ?.takeIf { it.isNotNullOrBlank() }
                 return findForcedTrack(candidates, subtitleLanguage, audioStreamLang)
             } else if (itemPlayback?.subtitleIndexEnabled == true) {
                 return candidates.firstOrNull { it.index == itemPlayback.subtitleIndex }
             } else {
-                val seriesLang =
-                    playbackLanguageChoice?.subtitleLanguage?.takeIf { it.isNotNullOrBlank() }
-                val subtitleLanguage =
-                    (seriesLang ?: userConfig?.subtitleLanguagePreference)
-                        ?.takeIf { it.isNotNullOrBlank() }
-
                 val subtitleMode =
                     when {
                         playbackLanguageChoice?.subtitlesDisabled == false && seriesLang != null -> {
@@ -258,9 +273,17 @@ class StreamChoiceService
 
                         else -> {
                             // Fallback to the user's preference
-                            userConfig?.subtitleMode ?: SubtitlePlaybackMode.DEFAULT
+                            when (prefs.userPreferences?.subtitleMode) {
+                                SubtitleModePreference.USE_USER_PROFILE -> userConfig?.subtitleMode
+                                SubtitleModePreference.DEFAULT -> SubtitlePlaybackMode.DEFAULT
+                                SubtitleModePreference.SMART -> SubtitlePlaybackMode.SMART
+                                SubtitleModePreference.ONLY_FORCED -> SubtitlePlaybackMode.ONLY_FORCED
+                                SubtitleModePreference.ALWAYS -> SubtitlePlaybackMode.ALWAYS
+                                SubtitleModePreference.NONE -> SubtitlePlaybackMode.NONE
+                                null -> SubtitlePlaybackMode.DEFAULT
+                            }
                         }
-                    }
+                    } ?: SubtitlePlaybackMode.DEFAULT
                 val candidates =
                     candidates
                         .sortedWith(

app/src/main/java/com/github/damontecres/wholphin/services/UserPreferencesService.kt

@@ -4,8 +4,9 @@ import androidx.datastore.core.DataStore
 import com.github.damontecres.wholphin.data.ServerRepository
 import com.github.damontecres.wholphin.preferences.AppPreferences
 import com.github.damontecres.wholphin.preferences.UserPreferences
-import kotlinx.coroutines.flow.firstOrNull
-import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.first
 import javax.inject.Inject
 import javax.inject.Singleton
 
@@ -19,13 +20,10 @@ class UserPreferencesService
         private val serverRepository: ServerRepository,
         private val preferencesDataStore: DataStore<AppPreferences>,
     ) {
-        val flow = preferencesDataStore.data.map { UserPreferences(it) }
-
-        suspend fun getCurrent(): UserPreferences =
-            serverRepository.currentUserDto!!.configuration.let { userConfig ->
-                val appPrefs = preferencesDataStore.data.firstOrNull() ?: AppPreferences.getDefaultInstance()
-                UserPreferences(
-                    appPrefs,
-                )
+        val flow: Flow<UserPreferences> =
+            preferencesDataStore.data.combine(serverRepository.currentUserFlow) { appPrefs, user ->
+                UserPreferences(appPrefs, user?.appPreferences)
             }
+
+        suspend fun getCurrent(): UserPreferences = flow.first()
     }