feat(D-01/E): quickwins — debug toggle, HumanChairHelper move, collar equip

Q1: Remove F9 debug toggle from GltfAnimationApplier + delete dead
    GltfRenderLayer + remove keybind registration

Q2: Move HumanChairHelper from state/ to util/ — pure utility with
    no state dependency. 7 import updates.

Q3: Wire NECK collar equip flow in DataDrivenBondageItem:
    - Target must be tied up (V1 rule preserved)
    - Distance + line-of-sight validation
    - Owner added to NBT before equip via CollarHelper.addOwner()
    - V2EquipmentHelper handles conflict resolution
    - ModSounds.COLLAR_PUT played on success
    - OwnershipComponent.onEquipped registers in CollarRegistry

src/main/java/com/tiedup/remake/client/animation/render/DogPoseRenderHandler.java

@@ -3,7 +3,7 @@ package com.tiedup.remake.client.animation.render;
 import com.tiedup.remake.core.TiedUpMod;
 import com.tiedup.remake.items.base.PoseType;
 import com.tiedup.remake.v2.bondage.PoseTypeHelper;
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;

src/main/java/com/tiedup/remake/client/animation/render/PetBedRenderHandler.java

@@ -4,7 +4,7 @@ import com.tiedup.remake.client.state.PetBedClientState;
 import com.tiedup.remake.core.TiedUpMod;
 import com.tiedup.remake.items.base.PoseType;
 import com.tiedup.remake.v2.bondage.PoseTypeHelper;
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import net.minecraft.client.player.AbstractClientPlayer;

src/main/java/com/tiedup/remake/client/animation/tick/AnimationTickHandler.java

@@ -17,7 +17,7 @@ import com.tiedup.remake.client.state.PetBedClientState;
 import com.tiedup.remake.items.base.PoseType;
 import com.tiedup.remake.v2.bondage.BindModeHelper;
 import com.tiedup.remake.v2.bondage.PoseTypeHelper;
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import com.tiedup.remake.v2.bondage.IV2BondageEquipment;

src/main/java/com/tiedup/remake/client/gltf/GltfAnimationApplier.java

@@ -13,8 +13,6 @@ import java.util.Set;
 import java.util.TreeSet;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.player.AbstractClientPlayer;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.entity.LivingEntity;
 import net.minecraftforge.api.distmarker.Dist;
@@ -433,52 +431,6 @@ public final class GltfAnimationApplier {
         ContextAnimationFactory.clearCache();
     }
 
-    // LEGACY F9 DEBUG TOGGLE
-
-    private static boolean debugEnabled = false;
-
-    /**
-     * Toggle debug mode via F9 key.
-     * When enabled, applies handcuffs V2 animation (rightArm + leftArm) to the local player
-     * using STAND_IDLE context. When disabled, clears all V2 animation.
-     */
-    public static void toggle() {
-        debugEnabled = !debugEnabled;
-        LOGGER.info(
-            "[GltfPipeline] Debug toggle: {}",
-            debugEnabled ? "ON" : "OFF"
-        );
-
-        AbstractClientPlayer player = Minecraft.getInstance().player;
-        if (player == null) return;
-
-        if (debugEnabled) {
-            ResourceLocation modelLoc = ResourceLocation.fromNamespaceAndPath(
-                "tiedup",
-                "models/gltf/v2/handcuffs/cuffs_prototype.glb"
-            );
-            Set<String> armParts = Set.of("rightArm", "leftArm");
-            RegionBoneMapper.BoneOwnership debugOwnership =
-                new RegionBoneMapper.BoneOwnership(armParts, Set.of());
-            applyV2Animation(
-                player,
-                modelLoc,
-                null,
-                AnimationContext.STAND_IDLE,
-                debugOwnership
-            );
-        } else {
-            clearV2Animation(player);
-        }
-    }
-
-    /**
-     * Whether F9 debug mode is currently enabled.
-     */
-    public static boolean isEnabled() {
-        return debugEnabled;
-    }
-
     // INTERNAL
 
     /**

src/main/java/com/tiedup/remake/client/gltf/GltfClientSetup.java

@@ -1,11 +1,9 @@
 package com.tiedup.remake.client.gltf;
 
-import com.mojang.blaze3d.platform.InputConstants;
 import com.tiedup.remake.client.animation.context.ContextAnimationFactory;
 import com.tiedup.remake.client.animation.context.ContextGlbRegistry;
 import com.tiedup.remake.v2.bondage.client.V2BondageRenderLayer;
 import com.tiedup.remake.v2.bondage.datadriven.DataDrivenItemReloadListener;
-import net.minecraft.client.KeyMapping;
 import net.minecraft.client.renderer.entity.player.PlayerRenderer;
 import net.minecraft.server.packs.resources.ResourceManager;
 import net.minecraft.server.packs.resources.SimplePreparableReloadListener;
@@ -13,8 +11,6 @@ import net.minecraft.util.profiling.ProfilerFiller;
 import net.minecraftforge.api.distmarker.Dist;
 import net.minecraftforge.client.event.EntityRenderersEvent;
 import net.minecraftforge.client.event.RegisterClientReloadListenersEvent;
-import net.minecraftforge.client.event.RegisterKeyMappingsEvent;
-import net.minecraftforge.event.TickEvent;
 import net.minecraftforge.eventbus.api.SubscribeEvent;
 import net.minecraftforge.fml.common.Mod;
 import net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent;
@@ -23,24 +19,16 @@ import org.apache.logging.log4j.Logger;
 
 /**
  * Forge event registration for the glTF pipeline.
- * Registers keybind (F9), render layers, and animation factory.
+ * Registers render layers and animation factory.
  */
 public final class GltfClientSetup {
 
     private static final Logger LOGGER = LogManager.getLogger("GltfPipeline");
 
-    private static final String KEY_CATEGORY = "key.categories.tiedup";
-    static final KeyMapping TOGGLE_KEY = new KeyMapping(
-        "key.tiedup.gltf_toggle",
-        InputConstants.Type.KEYSYM,
-        InputConstants.KEY_F9,
-        KEY_CATEGORY
-    );
-
     private GltfClientSetup() {}
 
     /**
-     * MOD bus event subscribers (FMLClientSetupEvent, RegisterKeyMappings, AddLayers).
+     * MOD bus event subscribers (FMLClientSetupEvent, AddLayers).
      */
     @Mod.EventBusSubscriber(
         modid = "tiedup",
@@ -58,21 +46,11 @@ public final class GltfClientSetup {
             });
         }
 
-        @SubscribeEvent
-        public static void onRegisterKeybindings(
-            RegisterKeyMappingsEvent event
-        ) {
-            event.register(TOGGLE_KEY);
-            LOGGER.info("[GltfPipeline] Keybind registered: F9");
-        }
-
         @SuppressWarnings("unchecked")
         @SubscribeEvent
         public static void onAddLayers(EntityRenderersEvent.AddLayers event) {
-            // Add GltfRenderLayer (prototype/debug with F9 toggle) to player renderers
             var defaultRenderer = event.getSkin("default");
             if (defaultRenderer instanceof PlayerRenderer playerRenderer) {
-                playerRenderer.addLayer(new GltfRenderLayer(playerRenderer));
                 playerRenderer.addLayer(
                     new V2BondageRenderLayer<>(playerRenderer)
                 );
@@ -81,10 +59,9 @@ public final class GltfClientSetup {
                 );
             }
 
-            // Add both layers to slim player renderer (Alex)
+            // Add V2 layer to slim player renderer (Alex)
             var slimRenderer = event.getSkin("slim");
             if (slimRenderer instanceof PlayerRenderer playerRenderer) {
-                playerRenderer.addLayer(new GltfRenderLayer(playerRenderer));
                 playerRenderer.addLayer(
                     new V2BondageRenderLayer<>(playerRenderer)
                 );
@@ -143,23 +120,4 @@ public final class GltfClientSetup {
         }
     }
 
-    /**
-     * FORGE bus event subscribers (ClientTickEvent for keybind toggle).
-     */
-    @Mod.EventBusSubscriber(
-        modid = "tiedup",
-        bus = Mod.EventBusSubscriber.Bus.FORGE,
-        value = Dist.CLIENT
-    )
-    public static class ForgeBusEvents {
-
-        @SubscribeEvent
-        public static void onClientTick(TickEvent.ClientTickEvent event) {
-            if (event.phase != TickEvent.Phase.END) return;
-
-            while (TOGGLE_KEY.consumeClick()) {
-                GltfAnimationApplier.toggle();
-            }
-        }
-    }
 }

src/main/java/com/tiedup/remake/client/gltf/GltfRenderLayer.java

@@ -1,106 +0,0 @@
-package com.tiedup.remake.client.gltf;
-
-import com.mojang.blaze3d.vertex.PoseStack;
-import net.minecraft.client.Minecraft;
-import net.minecraft.client.model.PlayerModel;
-import net.minecraft.client.player.AbstractClientPlayer;
-import net.minecraft.client.renderer.MultiBufferSource;
-import net.minecraft.client.renderer.entity.RenderLayerParent;
-import net.minecraft.client.renderer.entity.layers.RenderLayer;
-import net.minecraft.resources.ResourceLocation;
-import net.minecraftforge.api.distmarker.Dist;
-import net.minecraftforge.api.distmarker.OnlyIn;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.Logger;
-import org.joml.Matrix4f;
-
-/**
- * RenderLayer that renders the glTF mesh (handcuffs) on the player.
- * Only active when enabled and only renders on the local player.
- * <p>
- * Uses the live skinning path: reads live skeleton from HumanoidModel
- * via {@link GltfLiveBoneReader}, following PlayerAnimator + bendy-lib rotations.
- * Falls back to GLB-internal skinning via {@link GltfSkinningEngine} if live reading fails.
- */
-@OnlyIn(Dist.CLIENT)
-public class GltfRenderLayer
-    extends RenderLayer<AbstractClientPlayer, PlayerModel<AbstractClientPlayer>>
-{
-
-    private static final Logger LOGGER = LogManager.getLogger("GltfPipeline");
-
-    private static final ResourceLocation CUFFS_MODEL =
-        ResourceLocation.fromNamespaceAndPath(
-            "tiedup",
-            "models/gltf/v2/handcuffs/cuffs_prototype.glb"
-        );
-
-    public GltfRenderLayer(
-        RenderLayerParent<
-            AbstractClientPlayer,
-            PlayerModel<AbstractClientPlayer>
-        > renderer
-    ) {
-        super(renderer);
-    }
-
-    /**
-     * The Y translate offset to place the glTF mesh in the MC PoseStack.
-     * <p>
-     * After LivingEntityRenderer's scale(-1,-1,1) + translate(0,-1.501,0),
-     * the PoseStack origin is at the model top (1.501 blocks above feet), Y-down.
-     * The glTF mesh (MC-converted) has feet at Y=0 and head at Y≈-1.5.
-     * Translating by 1.501 maps glTF feet to PoseStack feet and head to top.
-     */
-    private static final float ALIGNMENT_Y = 1.501f;
-
-    @Override
-    public void render(
-        PoseStack poseStack,
-        MultiBufferSource buffer,
-        int packedLight,
-        AbstractClientPlayer entity,
-        float limbSwing,
-        float limbSwingAmount,
-        float partialTick,
-        float ageInTicks,
-        float netHeadYaw,
-        float headPitch
-    ) {
-        if (!GltfAnimationApplier.isEnabled()) return;
-        if (entity != Minecraft.getInstance().player) return;
-
-        GltfData data = GltfCache.get(CUFFS_MODEL);
-        if (data == null) return;
-
-        // Live path: read skeleton from HumanoidModel (after PlayerAnimator)
-        PlayerModel<AbstractClientPlayer> parentModel = this.getParentModel();
-        Matrix4f[] joints = GltfLiveBoneReader.computeJointMatricesFromModel(
-            parentModel,
-            data,
-            entity
-        );
-        if (joints == null) {
-            // Fallback to GLB-internal path if live reading fails
-            joints = GltfSkinningEngine.computeJointMatrices(data);
-        }
-
-        poseStack.pushPose();
-
-        // Align glTF mesh with MC model (feet-to-feet alignment)
-        poseStack.translate(0, ALIGNMENT_Y, 0);
-
-        GltfMeshRenderer.renderSkinned(
-            data,
-            joints,
-            poseStack,
-            buffer,
-            packedLight,
-            net.minecraft.client.renderer.entity.LivingEntityRenderer.getOverlayCoords(
-                entity,
-                0.0f
-            )
-        );
-        poseStack.popPose();
-    }
-}

src/main/java/com/tiedup/remake/entities/EntityMaster.java

@@ -1072,7 +1072,7 @@ public class EntityMaster extends EntityKidnapperElite {
                             if (
                                 tag != null &&
                                 tag.getBoolean(
-                                    com.tiedup.remake.state.HumanChairHelper.NBT_KEY
+                                    com.tiedup.remake.util.HumanChairHelper.NBT_KEY
                                 )
                             ) {
                                 bindState.unequip(BodyRegionV2.ARMS);

src/main/java/com/tiedup/remake/entities/ai/master/MasterHumanChairGoal.java

@@ -5,7 +5,7 @@ import com.tiedup.remake.dialogue.DialogueBridge;
 import com.tiedup.remake.entities.EntityMaster;
 import com.tiedup.remake.v2.bondage.datadriven.DataDrivenBondageItem;
 import net.minecraft.resources.ResourceLocation;
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import java.util.EnumSet;

src/main/java/com/tiedup/remake/mixin/MixinLivingEntityBodyRot.java

@@ -1,6 +1,6 @@
 package com.tiedup.remake.mixin;
 
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import net.minecraft.world.entity.LivingEntity;

src/main/java/com/tiedup/remake/mixin/client/MixinCamera.java

@@ -2,7 +2,7 @@ package com.tiedup.remake.mixin.client;
 
 import com.tiedup.remake.items.base.PoseType;
 import com.tiedup.remake.v2.bondage.PoseTypeHelper;
-import com.tiedup.remake.state.HumanChairHelper;
+import com.tiedup.remake.util.HumanChairHelper;
 import com.tiedup.remake.state.PlayerBindState;
 import com.tiedup.remake.v2.BodyRegionV2;
 import net.minecraft.client.Camera;

src/main/java/com/tiedup/remake/util/HumanChairHelper.java

@@ -1,4 +1,4 @@
-package com.tiedup.remake.state;
+package com.tiedup.remake.util;
 
 import com.tiedup.remake.items.base.PoseType;
 import net.minecraft.nbt.CompoundTag;

src/main/java/com/tiedup/remake/v2/bondage/client/V2BondageRenderLayer.java

@@ -46,9 +46,7 @@ import org.joml.Matrix4f;
  * pushPose/popPose pair. Joint matrices are computed per-GLB-model
  * because different GLB models have different skeletons.
  *
- * <p>Unlike {@link com.tiedup.remake.client.gltf.GltfRenderLayer},
- * this layer is always active (no F9 toggle guard) and renders on
- * ALL entities (no local-player-only guard).
+ * <p>This layer is always active and renders on ALL entities.
  */
 @OnlyIn(Dist.CLIENT)
 public class V2BondageRenderLayer<

src/main/java/com/tiedup/remake/v2/bondage/datadriven/DataDrivenBondageItem.java

@@ -1,7 +1,12 @@
 package com.tiedup.remake.v2.bondage.datadriven;
 
+import com.tiedup.remake.core.ModSounds;
 import com.tiedup.remake.core.TiedUpMod;
+import com.tiedup.remake.state.IRestrainable;
+import com.tiedup.remake.util.KidnappedHelper;
 import com.tiedup.remake.v2.BodyRegionV2;
+import com.tiedup.remake.v2.bondage.CollarHelper;
+import com.tiedup.remake.v2.bondage.V2EquipResult;
 import com.tiedup.remake.v2.bondage.BindModeHelper;
 import com.tiedup.remake.v2.bondage.IV2BondageEquipment;
 import com.tiedup.remake.v2.bondage.TyingInteractionHelper;
@@ -168,11 +173,39 @@ public class DataDrivenBondageItem extends AbstractV2BondageItem {
             return TyingInteractionHelper.handleTying(serverPlayer, target, stack, hand);
         }
 
-        // NECK: blocked — collar equip requires owner setup (add owner to NBT,
-        // register in CollarRegistry, play sound, sync) which is not yet wired
-        // through interactLivingEntity. TODO: implement collar equip flow.
-        if (regions.contains(BodyRegionV2.NECK)) {
-            TiedUpMod.LOGGER.debug("[DataDrivenBondageItem] NECK equip via right-click not yet implemented");
+        // NECK: collar equip flow
+        if (regions.contains(BodyRegionV2.NECK) && player instanceof ServerPlayer serverPlayer) {
+            // Target must be tied up to collar (V1 rule preserved)
+            IRestrainable targetState = KidnappedHelper.getKidnappedState(target);
+            if (targetState == null || !targetState.isTiedUp()) {
+                return InteractionResult.PASS;
+            }
+
+            // Distance + line-of-sight
+            if (player.distanceTo(target) > 4.0 || !player.hasLineOfSight(target)) {
+                return InteractionResult.PASS;
+            }
+
+            // Add player as owner in NBT before equip
+            ItemStack collarCopy = stack.copy();
+            CollarHelper.addOwner(collarCopy, player);
+
+            // Equip via V2 system (handles conflict resolution, displaced items)
+            V2EquipResult result = V2EquipmentHelper.equipItem(target, collarCopy);
+            if (result.isSuccess()) {
+                for (ItemStack displaced : result.displaced()) {
+                    target.spawnAtLocation(displaced);
+                }
+                stack.shrink(1);
+                // Play collar equip sound
+                target.level().playSound(null, target.getX(), target.getY(), target.getZ(),
+                    ModSounds.COLLAR_PUT.get(),
+                    net.minecraft.sounds.SoundSource.PLAYERS, 0.5f, 1.0f);
+                V2EquipmentHelper.sync(target);
+                TiedUpMod.LOGGER.info("[DataDrivenBondageItem] {} collared {} (owner added)",
+                    player.getName().getString(), target.getName().getString());
+                return InteractionResult.SUCCESS;
+            }
             return InteractionResult.PASS;
         }