Update radio prefix parsing (#13777)

Content.Shared/Radio/Components/EncryptionKeyComponent.cs

@@ -0,0 +1,22 @@
+using Content.Shared.Chat;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype.Set;
+
+namespace Content.Shared.Radio.Components;
+
+/// <summary>
+///     This component is currently used for providing access to channels for "HeadsetComponent"s.
+///     It should be used for intercoms and other radios in future.
+/// </summary>
+[RegisterComponent]
+public sealed class EncryptionKeyComponent : Component
+{
+    [DataField("channels", customTypeSerializer: typeof(PrototypeIdHashSetSerializer<RadioChannelPrototype>))]
+    public HashSet<string> Channels = new();
+
+    /// <summary>
+    ///     This is the channel that will be used when using the default/department prefix (<see cref="SharedChatSystem.DefaultChannelKey"/>).
+    /// </summary>
+    [DataField("defaultChannel", customTypeSerializer: typeof(PrototypeIdSerializer<RadioChannelPrototype>))]
+    public readonly string? DefaultChannel;
+}