refactor to unify data fetching and define abstract API for re-use

Jellyfin.Plugin.SRFPlay/Api/ISRFApiClientFactory.cs

@@ -0,0 +1,13 @@
+namespace Jellyfin.Plugin.SRFPlay.Api;
+
+/// <summary>
+/// Factory interface for creating SRF API clients.
+/// </summary>
+public interface ISRFApiClientFactory
+{
+    /// <summary>
+    /// Creates a new instance of the SRF API client.
+    /// </summary>
+    /// <returns>A new SRFApiClient instance.</returns>
+    SRFApiClient CreateClient();
+}