Fix emergency evac shuttle console early launch mispredict (#39751)

* Fix

* Yes

* Mess

* Update

* Like that?

Content.Shared/Shuttles/Systems/SharedEmergencyShuttleSystem.cs

@@ -0,0 +1,34 @@
+using Content.Shared.CCVar;
+using Content.Shared.Popups;
+using Content.Shared.Shuttles.Components;
+using Content.Shared.UserInterface;
+using Robust.Shared.Configuration;
+
+namespace Content.Shared.Shuttles.Systems;
+
+public abstract class SharedEmergencyShuttleSystem : EntitySystem
+{
+    [Dependency] protected readonly IConfigurationManager ConfigManager = default!;
+    [Dependency] protected readonly SharedPopupSystem Popup = default!;
+
+    private bool _emergencyEarlyLaunchAllowed;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<EmergencyShuttleConsoleComponent, ActivatableUIOpenAttemptEvent>(OnEmergencyOpenAttempt);
+
+        Subs.CVar(ConfigManager, CCVars.EmergencyEarlyLaunchAllowed, value => _emergencyEarlyLaunchAllowed = value, true);
+    }
+
+    private void OnEmergencyOpenAttempt(Entity<EmergencyShuttleConsoleComponent> ent, ref ActivatableUIOpenAttemptEvent args)
+    {
+        // I'm hoping ActivatableUI checks it's open before allowing these messages.
+        if (_emergencyEarlyLaunchAllowed)
+            return;
+
+        args.Cancel();
+        Popup.PopupClient(Loc.GetString("emergency-shuttle-console-no-early-launches"), ent, args.User);
+    }
+}