Refactor project files for improved readability and structure

- Cleaned up whitespace in Directory.Build.props and Directory.Packages.props for consistency.
- Reformatted project file references in PnvPanel.Api.csproj for better clarity.
- Enhanced code readability in various endpoint files by adjusting line breaks and indentation.
- Standardized method signatures and improved formatting in ResultExtensions and multiple endpoint classes for better maintainability.

backend/src/PnvPanel.Application/Configs/Create/CreateVpnConfigCommand.cs

@@ -3,4 +3,6 @@ using PnvPanel.Application.Common.Models;
 
 namespace PnvPanel.Application.Configs.Create;
 
-public sealed record CreateVpnConfigCommand(Guid InboundId, string? Label) : ICommand<Result<VpnConfigDto>>, IRequiresActivation;
+public sealed record CreateVpnConfigCommand(Guid InboundId, string? Label)
+    : ICommand<Result<VpnConfigDto>>,
+        IRequiresActivation;