Add Telegram bot integration and enhance user management features

- Introduced Telegram.Bot package for bot functionality.
- Updated user management to include Telegram linking and blocking features.
- Enhanced activation request handling with notifications via Telegram.
- Added new database entities for Telegram link tokens and login requests.
- Implemented traffic synchronization for client stats in the XuiPanelGateway.
- Updated application structure to support new test projects and improved dependency injection for Telegram services.

backend/tests/PnvPanel.Domain.Tests/Apps/ClientAppTests.cs

@@ -0,0 +1,34 @@
+using PnvPanel.Domain.Apps;
+using Xunit;
+
+namespace PnvPanel.Domain.Tests.Apps;
+
+public class ClientAppTests
+{
+    [Fact]
+    public void Create_SetsEnabledByDefault()
+    {
+        var app = ClientApp.Create("v2rayNG", new Uri("https://play.google.com/store/apps/details?id=x"), OsPlatform.Android, "desc", null, 1);
+
+        Assert.Equal("v2rayNG", app.Name);
+        Assert.Equal(OsPlatform.Android, app.OperatingSystem);
+        Assert.True(app.IsEnabled);
+        Assert.Equal(1, app.SortOrder);
+    }
+
+    [Fact]
+    public void Update_ReplacesAllMutableFields()
+    {
+        var app = ClientApp.Create("Old", new Uri("https://old.example.com"), OsPlatform.IOS, "old", "old-icon", 1);
+
+        app.Update("New", new Uri("https://new.example.com"), OsPlatform.MacOS, "new", "new-icon", 2, isEnabled: false);
+
+        Assert.Equal("New", app.Name);
+        Assert.Equal(new Uri("https://new.example.com"), app.DownloadUrl);
+        Assert.Equal(OsPlatform.MacOS, app.OperatingSystem);
+        Assert.Equal("new", app.Description);
+        Assert.Equal("new-icon", app.IconUrl);
+        Assert.Equal(2, app.SortOrder);
+        Assert.False(app.IsEnabled);
+    }
+}