Fix music artist listing & show music in collections (#1739)

## Description
Switches to use the Artists API instead of Items API when fetching the
list of artists in a library.

Enables fetching artists, albums, and music videos in a collection.

Also adds titles for the remaining `BaseItemKind` types for future
proofing even if they aren't used anywhere in the app.

### Related issues
Fixes #1733
Fixes #1734
Fixes #1735


### Testing
Emulator, created a new collection with the above. Also verified the
artist query against the web UI

## Screenshots
N/A

## AI or LLM usage
None

app/src/main/java/com/github/damontecres/wholphin/util/ApiRequestPager.kt

@@ -10,6 +10,7 @@ import kotlinx.serialization.modules.polymorphic
 import kotlinx.serialization.modules.subclass
 import org.jellyfin.sdk.api.client.ApiClient
 import org.jellyfin.sdk.api.client.Response
+import org.jellyfin.sdk.api.client.extensions.artistsApi
 import org.jellyfin.sdk.api.client.extensions.genresApi
 import org.jellyfin.sdk.api.client.extensions.itemsApi
 import org.jellyfin.sdk.api.client.extensions.liveTvApi
@@ -21,6 +22,7 @@ import org.jellyfin.sdk.api.client.extensions.tvShowsApi
 import org.jellyfin.sdk.api.client.extensions.userLibraryApi
 import org.jellyfin.sdk.model.api.BaseItemDtoQueryResult
 import org.jellyfin.sdk.model.api.GetProgramsDto
+import org.jellyfin.sdk.model.api.request.GetArtistsRequest
 import org.jellyfin.sdk.model.api.request.GetEpisodesRequest
 import org.jellyfin.sdk.model.api.request.GetGenresRequest
 import org.jellyfin.sdk.model.api.request.GetItemsRequest
@@ -367,6 +369,25 @@ object GetLiveTvChannelsRequestHandler : RequestHandler<GetLiveTvChannelsRequest
     ): Response<BaseItemDtoQueryResult> = api.liveTvApi.getLiveTvChannels(request)
 }
 
+@Serializable
+object GetArtistsHandler : RequestHandler<GetArtistsRequest> {
+    override fun prepare(
+        request: GetArtistsRequest,
+        startIndex: Int,
+        limit: Int,
+        enableTotalRecordCount: Boolean,
+    ): GetArtistsRequest =
+        request.copy(
+            startIndex = startIndex,
+            limit = limit,
+        )
+
+    override suspend fun execute(
+        api: ApiClient,
+        request: GetArtistsRequest,
+    ): Response<BaseItemDtoQueryResult> = api.artistsApi.getArtists((request))
+}
+
 val requestSerializersModule =
     SerializersModule {
         polymorphic(Any::class) {
@@ -382,5 +403,6 @@ val requestSerializersModule =
             subclass(GetStudiosRequest::class)
             subclass(GetRecordingsRequest::class)
             subclass(GetLiveTvChannelsRequest::class)
+            subclass(GetArtistsHandler::class)
         }
     }