[enhancement]: better version checks for lyrics, Navidrome (#529)

- Actually make serverfeatures partial
- Navidrome: only set multiple structured lyrics if extension exists
- Navidrome/Subsonic: minor type checking of OS extension (Navidrome implementation detail)
- Jellyfin: add separate knob for lyrics. Note, this should also probably be behind some version check...

src/renderer/api/subsonic/subsonic-controller.ts

@@ -384,10 +384,7 @@ const getServerInfo = async (args: ServerInfoArgs): Promise<ServerInfo> => {
         throw new Error('Failed to ping server');
     }
 
-    const features: ServerFeatures = {
-        smartPlaylists: false,
-        songLyrics: false,
-    };
+    const features: ServerFeatures = {};
 
     if (!ping.body.openSubsonic || !ping.body.serverVersion) {
         return { features, version: ping.body.version };
@@ -400,12 +397,14 @@ const getServerInfo = async (args: ServerInfoArgs): Promise<ServerInfo> => {
     }
 
     const subsonicFeatures: Record<string, number[]> = {};
-    for (const extension of res.body.openSubsonicExtensions) {
-        subsonicFeatures[extension.name] = extension.versions;
+    if (Array.isArray(res.body.openSubsonicExtensions)) {
+        for (const extension of res.body.openSubsonicExtensions) {
+            subsonicFeatures[extension.name] = extension.versions;
+        }
     }
 
     if (subsonicFeatures[SubsonicExtensions.SONG_LYRICS]) {
-        features.songLyrics = true;
+        features.multipleStructuredLyrics = true;
     }
 
     return { features, id: apiClientProps.server?.id, version: ping.body.serverVersion };