Refactor: Revert to hard deletes for messages. Remove IsDeleted flag and update repository and configurations accordingly.

Govor.Core/Repositories/Groups/IGroupsReader.cs

@@ -1,6 +1,10 @@
 namespace Govor.Core.Repositories.Groups;
 
-public class IGroupsReader
+public interface IGroupsReader // Changed to interface
 {
-    
+    Task<bool> ExistsAsync(Guid groupId);
+    Task<bool> IsUserMemberOfGroupAsync(Guid userId, Guid groupId);
+    // Potentially other read methods like:
+    // Task<ChatGroup?> GetByIdAsync(Guid groupId);
+    // Task<List<User>> GetGroupMembersAsync(Guid groupId);
 }

Govor.Core/Repositories/Groups/IGroupsRepository.cs

@@ -0,0 +1,7 @@
+namespace Govor.Core.Repositories.Groups;
+
+public interface IGroupsRepository : IGroupsReader
+{
+    // This interface will combine IGroupsReader and IGroupsWriter (once created)
+    // For now, it only includes IGroupsReader.
+}