[Revert] Reverts Ninja (#15516)

* Revert "[Antag] add space ninja as midround antag (#14069)"

This reverts commit c1cda0dbf8.

* Revert "[Fix] move ninja objectives into NinjaRole (#15490)"

This reverts commit 251f429fb3.

Content.Server/Objectives/Conditions/TerrorCondition.cs

@@ -1,52 +0,0 @@
-using Content.Server.Ninja.Systems;
-using Content.Server.Objectives.Interfaces;
-using Robust.Shared.Utility;
-
-namespace Content.Server.Objectives.Conditions;
-
-[DataDefinition]
-public sealed class TerrorCondition : IObjectiveCondition
-{
-    private Mind.Mind? _mind;
-
-    public IObjectiveCondition GetAssigned(Mind.Mind mind)
-    {
-        return new TerrorCondition {_mind = mind};
-    }
-
-    public string Title => Loc.GetString("objective-condition-terror-title");
-
-    public string Description => Loc.GetString("objective-condition-terror-description");
-
-    public SpriteSpecifier Icon => new SpriteSpecifier.Rsi(new ResourcePath("Structures/Machines/computers.rsi"), "comm_icon");
-
-    public float Progress
-    {
-        get
-        {
-            if (!NinjaSystem.GetNinjaRole(_mind, out var role))
-                return 0f;
-
-            return role.CalledInThreat ? 1f : 0f;
-        }
-    }
-
-    public float Difficulty => 2.75f;
-
-    public bool Equals(IObjectiveCondition? other)
-    {
-        return other is TerrorCondition cond && Equals(_mind, cond._mind);
-    }
-
-    public override bool Equals(object? obj)
-    {
-        if (ReferenceEquals(null, obj)) return false;
-        if (ReferenceEquals(this, obj)) return true;
-        return obj is TerrorCondition cond && cond.Equals(this);
-    }
-
-    public override int GetHashCode()
-    {
-        return _mind?.GetHashCode() ?? 0;
-    }
-}