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/CreateVpnConfigCommandHandler.cs

@@ -8,10 +8,16 @@ using PnvPanel.Domain.Configs;
 namespace PnvPanel.Application.Configs.Create;
 
 public sealed class CreateVpnConfigCommandHandler(
-    IAppDbContext dbContext, IIdentityService identityService, IXuiPanelGateway gateway, ICurrentUser currentUser)
-    : ICommandHandler<CreateVpnConfigCommand, Result<VpnConfigDto>>
+    IAppDbContext dbContext,
+    IIdentityService identityService,
+    IXuiPanelGateway gateway,
+    ICurrentUser currentUser
+) : ICommandHandler<CreateVpnConfigCommand, Result<VpnConfigDto>>
 {
-    public async Task<Result<VpnConfigDto>> Handle(CreateVpnConfigCommand command, CancellationToken cancellationToken)
+    public async Task<Result<VpnConfigDto>> Handle(
+        CreateVpnConfigCommand command,
+        CancellationToken cancellationToken
+    )
     {
         if (currentUser.UserId is not { } userId)
             return Result.Failure<VpnConfigDto>(AuthErrors.Unauthorized);
@@ -20,7 +26,8 @@ public sealed class CreateVpnConfigCommandHandler(
         if (profile is null)
             return Result.Failure<VpnConfigDto>(AuthErrors.Unauthorized);
 
-        var inbound = await dbContext.Inbounds.AsNoTracking()
+        var inbound = await dbContext
+            .Inbounds.AsNoTracking()
             .FirstOrDefaultAsync(i => i.Id == command.InboundId, cancellationToken);
 
         if (inbound is null || !inbound.IsPublished)
@@ -29,19 +36,32 @@ public sealed class CreateVpnConfigCommandHandler(
         if (!inbound.AllowedRoleIds.Contains(profile.RoleId))
             return Result.Failure<VpnConfigDto>(ConfigErrors.InboundNotAllowedForRole);
 
-        var node = await dbContext.Nodes.AsNoTracking().FirstOrDefaultAsync(n => n.Id == inbound.NodeId, cancellationToken);
+        var node = await dbContext
+            .Nodes.AsNoTracking()
+            .FirstOrDefaultAsync(n => n.Id == inbound.NodeId, cancellationToken);
         if (node is null || !node.IsEnabled)
             return Result.Failure<VpnConfigDto>(ConfigErrors.NodeDisabled);
 
         var config = VpnConfig.Create(userId, inbound.Id, inbound.Protocol, command.Label);
 
-        var reserveResult = await ReserveQuotaSlotAsync(userId, profile.MaxConfigs, config, cancellationToken);
+        var reserveResult = await ReserveQuotaSlotAsync(
+            userId,
+            profile.MaxConfigs,
+            config,
+            cancellationToken
+        );
         if (!reserveResult.IsSuccess)
             return Result.Failure<VpnConfigDto>(reserveResult.Error);
 
         var addResult = await gateway.AddClientAsync(
-            node, inbound.RemoteInboundId, inbound.Protocol, config.ClientEmail,
-            config.Label ?? config.ClientEmail, profile.MaxIpLimit, cancellationToken);
+            node,
+            inbound.RemoteInboundId,
+            inbound.Protocol,
+            config.ClientEmail,
+            config.Label ?? config.ClientEmail,
+            profile.MaxIpLimit,
+            cancellationToken
+        );
 
         if (!addResult.IsSuccess)
         {
@@ -64,15 +84,26 @@ public sealed class CreateVpnConfigCommandHandler(
     /// НЕ на время внешнего HTTP-вызова к 3x-ui — иначе рискуем держать соединение к БД открытым
     /// на секунды под внешним I/O.
     /// </summary>
-    private async Task<Result> ReserveQuotaSlotAsync(Guid userId, int maxConfigs, VpnConfig config, CancellationToken cancellationToken)
+    private async Task<Result> ReserveQuotaSlotAsync(
+        Guid userId,
+        int maxConfigs,
+        VpnConfig config,
+        CancellationToken cancellationToken
+    )
     {
-        await using var transaction = await dbContext.Database.BeginTransactionAsync(cancellationToken);
+        await using var transaction = await dbContext.Database.BeginTransactionAsync(
+            cancellationToken
+        );
 
         await dbContext.Database.ExecuteSqlInterpolatedAsync(
-            $"SELECT pg_advisory_xact_lock(hashtext({userId.ToString()}))", cancellationToken);
+            $"SELECT pg_advisory_xact_lock(hashtext({userId.ToString()}))",
+            cancellationToken
+        );
 
-        var activeCount = await dbContext.VpnConfigs
-            .CountAsync(c => c.UserId == userId && c.Status == ConfigStatus.Active, cancellationToken);
+        var activeCount = await dbContext.VpnConfigs.CountAsync(
+            c => c.UserId == userId && c.Status == ConfigStatus.Active,
+            cancellationToken
+        );
 
         if (maxConfigs != RoleQuota.Unlimited && activeCount >= maxConfigs)
         {