feat: implement Blazor web interface for GM session management

- Created GmRelay.Web project (Blazor Server)
- Created GmRelay.Shared library for domain models and rendering
- Refactored GmRelay.Bot to use the Shared library
- Integrated Telegram Login widget with server-side HMAC verification
- Added Dashboard, Group Details, and Edit Session pages
- Enabled bot notifications and in-place message updates from web actions
- Updated .NET Aspire orchestration and Docker Compose configuration

src/GmRelay.Bot/Features/Sessions/CreateSession/JoinSessionHandler.cs

@@ -3,7 +3,8 @@ using Npgsql;
 using Telegram.Bot;
 using Telegram.Bot.Types;
 using Telegram.Bot.Types.ReplyMarkups;
-using GmRelay.Bot.Domain;
+using GmRelay.Shared.Domain;
+using GmRelay.Shared.Rendering;
 
 namespace GmRelay.Bot.Features.Sessions.CreateSession;