Add ghost role raffles (#26629)

* Add ghost role raffles

* GRR: Fix dialogue sizing, fix merge

* GRR: Add raffle deciders (winner picker)

* GRR: Make settings prototype based with option to override

* GRR: Use Raffles folder and namespace

* GRR: DataFieldify and TimeSpanify

* GRR: Don't actually DataFieldify HashSet<ICommonSession>s

* GRR: add GetGhostRoleCount() + docs

* update engine on branch

* Ghost role raffles: docs, fix window size, cleanup, etc

* GRR: Admin UI

* GRR: Admin UI: Display initial/max/ext of selected raffle settings proto

* GRR: Make a ton of roles raffled

Content.Server/Ghost/Roles/Raffles/RngGhostRoleRaffleDecider.cs

@@ -0,0 +1,27 @@
+using System.Linq;
+using JetBrains.Annotations;
+using Robust.Shared.Player;
+using Robust.Shared.Random;
+
+namespace Content.Server.Ghost.Roles.Raffles;
+
+/// <summary>
+/// Chooses the winner of a ghost role raffle entirely randomly, without any weighting.
+/// </summary>
+[UsedImplicitly(ImplicitUseTargetFlags.WithMembers)]
+public sealed partial class RngGhostRoleRaffleDecider : IGhostRoleRaffleDecider
+{
+    public void PickWinner(IEnumerable<ICommonSession> candidates, Func<ICommonSession, bool> tryTakeover)
+    {
+        var random = IoCManager.Resolve<IRobustRandom>();
+
+        var choices = candidates.ToList();
+        random.Shuffle(choices); // shuffle the list so we can pick a lucky winner!
+
+        foreach (var candidate in choices)
+        {
+            if (tryTakeover(candidate))
+                return;
+        }
+    }
+}