Use archived gas mixture in gas exchange comparison (#32088)

The comparison for doing gas exchange used current and not archived
moles. This could lead to update order-dependent gas spreading effects.

To fix this, convert TileAtmosphere's MolesArchived and
TemperatureArchived to a AirArchived, and use that in the comparison
method.

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Co-authored-by: PraxisMapper <praxismapper@gmail.com>
Co-authored-by: Kevin Zheng <kevinz5000@gmail.com>

Content.Server/Atmos/EntitySystems/AtmosphereSystem.GridAtmosphere.cs

@@ -270,7 +270,7 @@ public sealed partial class AtmosphereSystem
     {
         DebugTools.AssertNotNull(tile.Air);
         DebugTools.Assert(tile.Air?.Immutable == false);
-        Array.Clear(tile.MolesArchived);
+        tile.AirArchived = null;
         tile.ArchivedCycle = 0;
 
         var count = 0;