Use interfaces in app host constructors

Emby.Server.Implementations/ApplicationHost.cs

@@ -192,7 +192,7 @@ namespace Emby.Server.Implementations
         /// Gets or sets the application paths.
         /// </summary>
         /// <value>The application paths.</value>
-        protected ServerApplicationPaths ApplicationPaths { get; set; }
+        protected IServerApplicationPaths ApplicationPaths { get; set; }
 
         /// <summary>
         /// Gets or sets all concrete types.
@@ -236,7 +236,7 @@ namespace Emby.Server.Implementations
         /// Initializes a new instance of the <see cref="ApplicationHost" /> class.
         /// </summary>
         public ApplicationHost(
-            ServerApplicationPaths applicationPaths,
+            IServerApplicationPaths applicationPaths,
             ILoggerFactory loggerFactory,
             IStartupOptions options,
             IFileSystem fileSystem,

Jellyfin.Server/CoreAppHost.cs

@@ -9,6 +9,7 @@ using Jellyfin.Server.Implementations;
 using Jellyfin.Server.Implementations.Activity;
 using Jellyfin.Server.Implementations.Users;
 using MediaBrowser.Common.Net;
+using MediaBrowser.Controller;
 using MediaBrowser.Controller.Drawing;
 using MediaBrowser.Controller.Library;
 using MediaBrowser.Model.Activity;
@@ -33,9 +34,9 @@ namespace Jellyfin.Server
         /// <param name="fileSystem">The <see cref="IFileSystem" /> to be used by the <see cref="CoreAppHost" />.</param>
         /// <param name="networkManager">The <see cref="INetworkManager" /> to be used by the <see cref="CoreAppHost" />.</param>
         public CoreAppHost(
-            ServerApplicationPaths applicationPaths,
+            IServerApplicationPaths applicationPaths,
             ILoggerFactory loggerFactory,
-            StartupOptions options,
+            IStartupOptions options,
             IFileSystem fileSystem,
             INetworkManager networkManager)
             : base(