Add Full system backup feature (#13945)

src/Jellyfin.Database/Jellyfin.Database.Implementations/Entities/TrickplayInfo.cs

@@ -14,7 +14,6 @@ public class TrickplayInfo
     /// <remarks>
     /// Required.
     /// </remarks>
-    [JsonIgnore]
     public Guid ItemId { get; set; }
 
     /// <summary>

src/Jellyfin.Database/Jellyfin.Database.Implementations/Entities/User.cs

@@ -61,7 +61,6 @@ namespace Jellyfin.Database.Implementations.Entities
         /// <remarks>
         /// Identity, Indexed, Required.
         /// </remarks>
-        [JsonIgnore]
         public Guid Id { get; set; }
 
         /// <summary>

src/Jellyfin.Database/Jellyfin.Database.Implementations/IJellyfinDatabaseProvider.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.EntityFrameworkCore;
@@ -62,4 +63,12 @@ public interface IJellyfinDatabaseProvider
     /// <param name="cancellationToken">A cancellation token.</param>
     /// <returns>A <see cref="Task"/> representing the result of the asynchronous operation.</returns>
     Task RestoreBackupFast(string key, CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Removes all contents from the database.
+    /// </summary>
+    /// <param name="dbContext">The Database context.</param>
+    /// <param name="tableNames">The names of the tables to purge or null for all tables to be purged.</param>
+    /// <returns>A Task.</returns>
+    Task PurgeDatabase(JellyfinDbContext dbContext, IEnumerable<string>? tableNames);
 }