Access groups + aghost all access (#6671)

Content.Shared/Access/AccessGroupPrototype.cs

@@ -0,0 +1,19 @@
+using Content.Shared.Access.Components;
+using Robust.Shared.Prototypes;
+using Robust.Shared.Serialization.TypeSerializers.Implementations.Custom.Prototype.Set;
+
+namespace Content.Shared.Access;
+
+/// <summary>
+///     Contains a list of access tags that are part of this group.
+///     Used by <see cref="AccessComponent"/> to avoid boilerplate.
+/// </summary>
+[Prototype("accessGroup")]
+public sealed class AccessGroupPrototype : IPrototype
+{
+    [DataField("id", required: true)]
+    public string ID { get; } = default!;
+
+    [DataField("tags", required: true, customTypeSerializer:typeof(PrototypeIdHashSetSerializer<AccessLevelPrototype>))]
+    public HashSet<string> Tags = default!;
+}