global radio toggle for observers (#22137)

Content.Server/Radio/Components/ActiveRadioComponent.cs

@@ -15,6 +15,13 @@ public sealed partial class ActiveRadioComponent : Component
     [DataField("channels", customTypeSerializer: typeof(PrototypeIdHashSetSerializer<RadioChannelPrototype>))]
     public HashSet<string> Channels = new();
 
+    /// <summary>
+    /// A toggle for globally receiving all radio channels.
+    /// Overrides <see cref="Channels"/>
+    /// </summary>
+    [DataField, ViewVariables(VVAccess.ReadWrite)]
+    public bool ReceiveAllChannels;
+
     /// <summary>
     ///     If this radio can hear all messages on all maps
     /// </summary>