Add audience categorization for shows: implement ShowAudience type, update related API endpoints, and enhance frontend components for audience selection and display. Modify data structures to support audience information in show creation and retrieval processes.

backend/src/TeleWave.Domain/Library/ShowAudience.cs

@@ -0,0 +1,14 @@
+namespace TeleWave.Domain.Library;
+
+/// <summary>Категория аудитории шоу (пригодится для фильтров/разграничения показа).</summary>
+public enum ShowAudience
+{
+    /// <summary>Обычное — без ограничений (по умолчанию).</summary>
+    General,
+
+    /// <summary>Детское.</summary>
+    Kids,
+
+    /// <summary>Взрослое.</summary>
+    Adult,
+}