Refactor messaging system to utilize LiteCqrs library

- Replaced instances of the previous messaging system with LiteCqrs across various application components, enhancing the CQRS implementation.
- Updated dependency injection to register LiteCqrs services and behaviors, streamlining command and query handling.
- Adjusted multiple command and query handlers to align with the new messaging framework, ensuring consistent functionality and improved maintainability.
- Added LiteCqrs package reference in the project file for better dependency management.

backend/Directory.Packages.props

@@ -29,6 +29,7 @@
     <PackageVersion Include="System.IdentityModel.Tokens.Jwt" Version="8.21.0" />
     <PackageVersion Include="Telegram.Bot" Version="22.10.2" />
     <PackageVersion Include="ThreeXui.Net" Version="1.0.4" />
+    <PackageVersion Include="LiteCqrs.Net" Version="1.0.1" />
     <!-- Тестирование (M8) -->
     <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.8.1" />
     <PackageVersion Include="xunit" Version="2.9.3" />