Add maximum atmos temperature limit (#22882)

* Add Tmax

* Increase Tmax

Content.Server/Atmos/GasMixture.cs

@@ -4,6 +4,7 @@ using System.Runtime.CompilerServices;
 using Content.Server.Atmos.Reactions;
 using Content.Shared.Atmos;
 using Robust.Shared.Serialization;
+using Robust.Shared.Utility;
 
 namespace Content.Server.Atmos
 {
@@ -58,8 +59,9 @@ namespace Content.Server.Atmos
             get => _temperature;
             set
             {
+                DebugTools.Assert(!float.IsNaN(_temperature));
                 if (Immutable) return;
-                _temperature = MathF.Max(value, Atmospherics.TCMB);
+                _temperature = MathF.Min(MathF.Max(value, Atmospherics.TCMB), Atmospherics.Tmax);
             }
         }
 

Content.Shared/Atmos/Atmospherics.cs

@@ -45,6 +45,15 @@ namespace Content.Shared.Atmos
         /// </summary>
         public const float T20C = 293.15f;
 
+        /// <summary>
+        ///     Do not allow any gas mixture temperatures to exceed this number. It is occasionally possible
+        ///     to have very small heat capacity (e.g. room that was just unspaced) and for large amounts of
+        ///     energy to be transferred to it, even for a brief moment. However, this messes up subsequent
+        ///     calculations and so cap it here. The physical interpretation is that at this temperature, any
+        ///     gas that you would have transforms into plasma.
+        /// </summary>
+        public const float Tmax = 200e3f;
+
         /// <summary>
         ///     Liters in a cell.
         /// </summary>