Update scheduling parameters and refactor channel endpoints: extend HorizonDays to 7 and RetentionDays to 90 in appsettings.json. Consolidate channel-related endpoint logic by removing obsolete files and enhancing the ShowEndpoints with audience and genre management capabilities. Improve error handling and streamline command handlers for channel operations.

backend/src/TeleWave.Application/Programming/Templates/RepeatSource.cs

@@ -0,0 +1,35 @@
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace TeleWave.Application.Programming.Templates;
+
+/// <summary>
+/// Откуда слот-повтор берёт содержимое: точка в уже записанной ленте того же канала. «Вечерний фильм
+/// утром в субботу» — это <c>daysAgo = 1, time = 20:00</c>.
+/// </summary>
+public sealed record RepeatSource(int DaysAgo, TimeOnly Time, int DurationMinutes)
+{
+    private static readonly JsonSerializerOptions Options = new()
+    {
+        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
+        DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
+        Converters = { new JsonStringEnumConverter() },
+    };
+
+    public string ToJson() => JsonSerializer.Serialize(this, Options);
+
+    public static RepeatSource? FromJson(string? json)
+    {
+        if (string.IsNullOrWhiteSpace(json))
+            return null;
+
+        try
+        {
+            return JsonSerializer.Deserialize<RepeatSource>(json, Options);
+        }
+        catch (JsonException)
+        {
+            return null;
+        }
+    }
+}