Clean repo for open source release

Remove build artifacts, dev tool configs, unused dependencies,
and third-party source dumps. Add proper README, update .gitignore,
clean up Makefile.

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

@@ -0,0 +1,83 @@
+package com.tiedup.remake.mixin.client;
+
+import com.tiedup.remake.client.animation.render.DogPoseRenderHandler;
+import com.tiedup.remake.v2.BodyRegionV2;
+import com.tiedup.remake.client.animation.util.DogPoseHelper;
+import com.tiedup.remake.items.base.ItemBind;
+import com.tiedup.remake.items.base.PoseType;
+import com.tiedup.remake.state.PlayerBindState;
+import net.minecraft.client.model.PlayerModel;
+import net.minecraft.client.player.AbstractClientPlayer;
+import net.minecraft.world.entity.LivingEntity;
+import net.minecraft.world.item.ItemStack;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+/**
+ * Mixin for PlayerModel to handle DOG pose head adjustments.
+ *
+ * When in DOG pose (body horizontal):
+ * - Head pitch offset so player looks forward
+ * - Head yaw converted to zRot (roll) since yRot axis is sideways when body is horizontal
+ */
+@Mixin(PlayerModel.class)
+public class MixinPlayerModel {
+
+    @Inject(method = "setupAnim", at = @At("TAIL"))
+    private void tiedup$adjustDogPose(
+        LivingEntity entity,
+        float limbSwing,
+        float limbSwingAmount,
+        float ageInTicks,
+        float netHeadYaw,
+        float headPitch,
+        CallbackInfo ci
+    ) {
+        if (!(entity instanceof AbstractClientPlayer player)) {
+            return;
+        }
+
+        PlayerBindState state = PlayerBindState.getInstance(player);
+        if (state == null) {
+            return;
+        }
+
+        ItemStack bind = state.getEquipment(BodyRegionV2.ARMS);
+        if (bind.isEmpty() || !(bind.getItem() instanceof ItemBind itemBind)) {
+            return;
+        }
+
+        if (itemBind.getPoseType() != PoseType.DOG) {
+            return;
+        }
+
+        PlayerModel<?> model = (PlayerModel<?>) (Object) this;
+
+        // === HEAD ROTATION FOR HORIZONTAL BODY ===
+        // Body is at -90° pitch (horizontal, face down)
+        // We apply a rotation delta to the poseStack in PlayerArmHideEventHandler
+        // The head needs to compensate for this transformation
+
+        float rotationDelta = DogPoseRenderHandler.getAppliedRotationDelta(
+            player.getId()
+        );
+        boolean moving = DogPoseRenderHandler.isDogPoseMoving(player.getId());
+
+        // netHeadYaw is head relative to vanilla body (yHeadRot - yBodyRot)
+        // We rotated the model by rotationDelta, so compensate:
+        // effectiveHeadYaw = netHeadYaw + rotationDelta
+        float headYaw = netHeadYaw + rotationDelta;
+
+        // Clamp based on movement state and apply head compensation
+        float maxYaw = moving ? 60f : 90f;
+        DogPoseHelper.applyHeadCompensationClamped(
+            model.head,
+            model.hat,
+            headPitch,
+            headYaw,
+            maxYaw
+        );
+    }
+}