Generalizes solution overflow & slightly increases space lube yield (#21094)

* generalize SolutionSpikeOverflowEvent

* let reactions overflow

* spacelube: 3 -> 5

* restore TryMixAndOverflow threshold cap

Content.Shared/Chemistry/Reaction/ChemicalReactionSystem.cs

@@ -262,12 +262,6 @@ namespace Content.Shared.Chemistry.Reaction
             if (products.Count == 0)
                 return true;
 
-            // remove excess product
-            // TODO spill excess?
-            var excessVolume = solution.Volume - maxVolume;
-            if (excessVolume > 0)
-                solution.RemoveSolution(excessVolume);
-
             // Add any reactions associated with the new products. This may re-add reactions that were already iterated
             // over previously. The new product may mean the reactions are applicable again and need to be processed.
             foreach (var product in products)
@@ -279,16 +273,10 @@ namespace Content.Shared.Chemistry.Reaction
             return true;
         }
 
-        /// <summary>
-        ///     Continually react a solution until no more reactions occur.
-        /// </summary>
-        public void FullyReactSolution(Solution solution, EntityUid owner) => FullyReactSolution(solution, owner, FixedPoint2.MaxValue, null);
-
         /// <summary>
         ///     Continually react a solution until no more reactions occur, with a volume constraint.
-        ///     If a reaction's products would exceed the max volume, some product is deleted.
         /// </summary>
-        public void FullyReactSolution(Solution solution, EntityUid owner, FixedPoint2 maxVolume, ReactionMixerComponent? mixerComponent)
+        public void FullyReactSolution(Solution solution, EntityUid owner, FixedPoint2 maxVolume, ReactionMixerComponent? mixerComponent = null)
         {
             // construct the initial set of reactions to check.
             SortedSet<ReactionPrototype> reactions = new();