reduce GC by skipping empty handlers in recipe handling

src/main/java/com/gregtechceu/gtceu/api/capability/recipe/CWURecipeCapability.java

@@ -32,6 +32,11 @@ public Integer copyWithModifier(Integer content, ContentModifier modifier) {
         return modifier.apply(content);
     }
 
+    @Override
+    public boolean skipEmptyContentCheck() {
+        return true;
+    }
+
     @Override
     public void addXEIInfo(WidgetGroup group, int xOffset, GTRecipe recipe, List<Content> contents, boolean perTick,
                            boolean isInput, MutableInt yOffset) {

src/main/java/com/gregtechceu/gtceu/api/capability/recipe/RecipeCapability.java

@@ -223,4 +223,13 @@ public boolean isTickSlot(int index, IO io, GTRecipe recipe) {
     public boolean shouldBypassDistinct() {
         return true;
     }
+
+    /**
+     * Should handlers of this capability be tried even when {@link IRecipeHandler#getTotalContentAmount()} is zero?
+     * E.g. should this capability bypass the empty handler optimization for rate-based capabilities.
+     * for example: CWU, where stored amount is zero but the handler can still provide computation.
+     */
+    public boolean skipEmptyContentCheck() {
+        return false;
+    }
 }

src/main/java/com/gregtechceu/gtceu/api/machine/trait/RecipeHandlerList.java

@@ -183,6 +183,10 @@ public Map<RecipeCapability<?>, List<Object>> handleRecipe(IO io, GTRecipe recip
             var entry = it.next();
             var handlerList = getCapability(entry.getKey());
             for (var handler : handlerList) {
+                if (io == IO.IN && handler.getTotalContentAmount() == 0 &&
+                        !handler.getCapability().skipEmptyContentCheck()) {
+                    continue;
+                }
                 var left = handler.handleRecipe(io, recipe, entry.getValue(), simulate);
                 if (left == null) {
                     it.remove();

src/main/java/com/gregtechceu/gtceu/api/recipe/RecipeHelper.java

@@ -219,6 +219,9 @@ public static ActionResult handleRecipe(IRecipeCapabilityHolder holder, GTRecipe
                                             Map<RecipeCapability<?>, List<Content>> contents,
                                             Map<RecipeCapability<?>, Object2IntMap<?>> chanceCaches,
                                             boolean isTick, boolean simulated) {
+        if (contents.isEmpty()) {
+            return ActionResult.PASS_NO_CONTENTS;
+        }
         RecipeRunner runner = new RecipeRunner(recipe, io, isTick, holder, chanceCaches, simulated);
         var result = runner.handle(contents);