Add grid auto-build functionality with profile management and preview capabilities

Implemented new API endpoints and frontend components for grid auto-building based on predefined profiles. Added functionality to list grid profiles, preview generated grids, and generate grids with specified parameters. Enhanced the TemplateEndpoints and related services to support these features, improving the user experience for channel scheduling. Localization updates were made to accommodate new features in both English and Russian.

backend/src/TeleWave.Infrastructure/DependencyInjection.cs

@@ -159,6 +159,7 @@ public static class DependencyInjection
         services.AddSingleton<IAudioProbe, FfprobeAudioProbe>();
         services.AddSingleton<IMediaProcessor, FfmpegMediaProcessor>();
         services.AddSingleton<IMediaProcessingQueue, MediaProcessingQueue>();
+        services.AddSingleton<IMediaProcessingLimits, MediaProcessingLimits>();
         services.AddSingleton<IBumperRenderQueue, BumperRenderQueue>();
 
         services.AddHostedService<MediaProcessingBackgroundService>();

backend/src/TeleWave.Infrastructure/Media/MediaProcessingLimits.cs

@@ -0,0 +1,13 @@
+using Microsoft.Extensions.Options;
+using TeleWave.Application.Common.Interfaces;
+
+namespace TeleWave.Infrastructure.Media;
+
+/// <summary>
+/// Читает параллельность транскода из настроек. Значение то же, по которому
+/// <see cref="MediaProcessingBackgroundService"/> раздаёт слоты, — иначе оценка очереди врала бы.
+/// </summary>
+public sealed class MediaProcessingLimits(IOptions<MediaOptions> options) : IMediaProcessingLimits
+{
+    public int MaxParallelTranscodes => Math.Max(1, options.Value.MaxParallelTranscodes);
+}