Enhance documentation with new features: added dark/light/system theme support, instructions page, and application catalog. Updated API and domain model for app management and automatic migrations on startup. Improved frontend structure with new routes and features for user instructions and app management.

backend/src/PnvPanel.Application/Configs/VpnConfigDto.cs

@@ -0,0 +1,17 @@
+using PnvPanel.Domain.Configs;
+using PnvPanel.Domain.Inbounds;
+
+namespace PnvPanel.Application.Configs;
+
+/// <summary>
+/// Пользователю показываем только DisplayName + протокол инбаунда — адрес/хост ноды и прочие
+/// детали 3x-ui в этот DTO не попадают (см. domain-model.md).
+/// </summary>
+public sealed record VpnConfigDto(
+    Guid Id, string? Label, VpnProtocol Protocol, string Location, int DeviceLimit,
+    long UsedUpBytes, long UsedDownBytes, DateTimeOffset? ExpiresAt, ConfigStatus Status, DateTimeOffset CreatedAt)
+{
+    public static VpnConfigDto FromDomain(VpnConfig config, Inbound inbound) => new(
+        config.Id, config.Label, config.Protocol, inbound.DisplayName ?? inbound.Remark, config.DeviceLimit,
+        config.UsedUpBytes, config.UsedDownBytes, config.ExpiresAt, config.Status, config.CreatedAt);
+}