fix: 修复数据库与SignalR无法连接的问题

server/src/Services/HttpVideoStreamService.cs

@@ -95,8 +95,6 @@ public class HttpVideoStreamService : BackgroundService
 {
     private static readonly NLog.Logger logger = NLog.LogManager.GetCurrentClassLogger();
 
-    private readonly IServiceProvider _serviceProvider;
-
     private HttpListener? _httpListener;
     private readonly int _serverPort = 4321;
 
@@ -109,11 +107,6 @@ public class HttpVideoStreamService : BackgroundService
     private readonly object _usbCameraLock = new object();
 #endif
 
-    public HttpVideoStreamService(IServiceProvider serviceProvider)
-    {
-        _serviceProvider = serviceProvider;
-    }
-
     private Optional<VideoStreamClient> TryGetClient(string boardId)
     {
         if (_clientDict.TryGetValue(boardId, out var client))
@@ -131,8 +124,7 @@ public class HttpVideoStreamService : BackgroundService
             return client;
         }
 
-        using var scope = _serviceProvider.CreateScope();
-        var userManager = scope.ServiceProvider.GetRequiredService<Database.UserManager>();
+        var userManager = new Database.UserManager();
 
         var boardRet = userManager.GetBoardByID(Guid.Parse(boardId));
         if (!boardRet.IsSuccessful || !boardRet.Value.HasValue)